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GROUNDWATER FLOW MODELS C. P. Kumar
E-Print Network [OSTI]
(Uttaranchal) 1.0 INTRODUCTION The use of groundwater models is prevalent in the field of environmental scienceGROUNDWATER FLOW MODELS C. P. Kumar Scientist `E1' National Institute of Hydrology Roorkee 247667, groundwater models are being applied to predict the transport of contaminants for risk evaluation. In general
Kumar, C.P.
155: Numerical Models of Groundwater Flow and Transport
155: Numerical Models of Groundwater Flow and Transport EKKEHARD HOLZBECHER1 AND SHAUL SOREK2 1. #12;2402 GROUNDWATER Calibration as a task cannot be separated from the other tasks. Inverse modeling of the Negev, J. Blaustein Institutes for Desert Research, Sede Boker, Israel The article gives an introduction
Sorek, Shaul
Validation Analysis of the Shoal Groundwater Flow and Transport Model
SciTech Connect (OSTI)
Environmental restoration at the Shoal underground nuclear test is following a process prescribed by a Federal Facility Agreement and Consent Order (FFACO) between the U.S. Department of Energy, the U.S. Department of Defense, and the State of Nevada. Characterization of the site included two stages of well drilling and testing in 1996 and 1999, and development and revision of numerical models of groundwater flow and radionuclide transport. Agreement on a contaminant boundary for the site and a corrective action plan was reached in 2006. Later that same year, three wells were installed for the purposes of model validation and site monitoring. The FFACO prescribes a five-year proof-of-concept period for demonstrating that the site groundwater model is capable of producing meaningful results with an acceptable level of uncertainty. The corrective action plan specifies a rigorous seven step validation process. The accepted groundwater model is evaluated using that process in light of the newly acquired data. The conceptual model of ground water flow for the Project Shoal Area considers groundwater flow through the fractured granite aquifer comprising the Sand Springs Range. Water enters the system by the infiltration of precipitation directly on the surface of the mountain range. Groundwater leaves the granite aquifer by flowing into alluvial deposits in the adjacent basins of Fourmile Flat and Fairview Valley. A groundwater divide is interpreted as coinciding with the western portion of the Sand Springs Range, west of the underground nuclear test, preventing flow from the test into Fourmile Flat. A very low conductivity shear zone east of the nuclear test roughly parallels the divide. The presence of these lateral boundaries, coupled with a regional discharge area to the northeast, is interpreted in the model as causing groundwater from the site to flow in a northeastward direction into Fairview Valley. Steady-state flow conditions are assumed given the absence of groundwater withdrawal activities in the area. The conceptual and numerical models were developed based upon regional hydrogeologic investigations conducted in the 1960s, site characterization investigations (including ten wells and various geophysical and geologic studies) at Shoal itself prior to and immediately after the test, and two site characterization campaigns in the 1990s for environmental restoration purposes (including eight wells and a year-long tracer test). The new wells are denoted MV-1, MV-2, and MV-3, and are located to the northnortheast of the nuclear test. The groundwater model was generally lacking data in the north-northeastern area; only HC-1 and the abandoned PM-2 wells existed in this area. The wells provide data on fracture orientation and frequency, water levels, hydraulic conductivity, and water chemistry for comparison with the groundwater model. A total of 12 real-number validation targets were available for the validation analysis, including five values of hydraulic head, three hydraulic conductivity measurements, three hydraulic gradient values, and one angle value for the lateral gradient in radians. In addition, the fracture dip and orientation data provide comparisons to the distributions used in the model and radiochemistry is available for comparison to model output. Goodness-of-fit analysis indicates that some of the model realizations correspond well with the newly acquired conductivity, head, and gradient data, while others do not. Other tests indicated that additional model realizations may be needed to test if the model input distributions need refinement to improve model performance. This approach (generating additional realizations) was not followed because it was realized that there was a temporal component to the data disconnect: the new head measurements are on the high side of the model distributions, but the heads at the original calibration locations themselves have also increased over time. This indicates that the steady-state assumption of the groundwater model is in error. To test the robustness of the model d
A. Hassan; J. Chapman
A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California
This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.
Joan B. Blainey; Claudia C. Faunt, and Mary C. Hill
ShowFlow: A practical interface for groundwater modeling
ShowFlow was created to provide a user-friendly, intuitive environment for researchers and students who use computer modeling software. What traditionally has been a workplace available only to those familiar with command-line based computer systems is now within reach of almost anyone interested in the subject of modeling. In the case of this edition of ShowFlow, the user can easily experiment with simulations using the steady state gaussian plume groundwater pollutant transport model SSGPLUME, though ShowFlow can be rewritten to provide a similar interface for any computer model. Included in this thesis is all the source code for both the ShowFlow application for Microsoft{reg sign} Windows{trademark} and the SSGPLUME model, a User's Guide, and a Developer's Guide for converting ShowFlow to run other model programs. 18 refs., 13 figs.
Tauxe, J.D.
modelling Groundwater flow Solute transport INTRODUCTION Predicting any natural process is a very difficultHYDROLOGICAL PROCESSES, VOL. 6, 369-395 (1992) STOCHASTIC MODELLING OF GROUNDWATER FLOW AND SOLUTE MODELLING Scales of heterogeneity, REV, dispersion and measurement scale groundwater flow and convection
Parameter Estimation in Groundwater Flow Models with Distributed and Pointwise Observations*
Parameter Estimation in Groundwater Flow Models with Distributed and Pointwise Observations* Ben G concerning the least sqaures estimation of parameters in a groundwater flow model. As is typically the case9310153. #12; 1 Introduction Understanding the flow of groundwater is an important scientific and engineering
COMSOL Modeling of Groundwater Flow and Contaminant Transport in Two-Dimensional Geometries With Heterogeneities
COMSOL Modeling of Groundwater Flow and Contaminant Transport in Two-Dimensional Geometries, Environmental Sys- tems. 1 Introduction Groundwater contributes an large portion of stream flow and subsequently% of a streams nitrogen load has been discharged from groundwater. The surficial aquifer geometry in this area
Gobbert, Matthias K.
Simulation of Nondifferentiable Models for Groundwater Flow and C. T. Kelleya
1 Simulation of Nondifferentiable Models for Groundwater Flow and Transport C. T. Kelleya K. R frequently in models for groundwater flow and species transport. The van Genuchten and Mualem PSK relations. INTRODUCTION Nonsmooth, even non-Lipschitz continuous, constitutive laws are not uncommon in models
1 THE APPLICATION OF THE LAND TRANSFORMATION, GROUNDWATER FLOW AND SOLUTE TRANSPORT MODELS). The two hydrogeologic models that are being used here allow us to explore the dynamics of groundwater flow Meeting, New Orleans, Louisiana, March 14, 2001. #12;2 INTRODUCTION Grand Traverse Bay and the Grand
Regional groundwater flow model for C, K. L. and P reactor areas, Savannah River Site, Aiken, SC
A regional groundwater flow model encompassing approximately 100 mi2 surrounding the C, K, L, and P reactor areas has been developed. The reactor flow model is designed to meet the planning objectives outlined in the General Groundwater Strategy for Reactor Area Projects by providing a common framework for analyzing groundwater flow, contaminant migration and remedial alternatives within the Reactor Projects team of the Environmental Restoration Department. The model provides a quantitative understanding of groundwater flow on a regional scale within the near surface aquifers and deeper semi-confined to confined aquifers. The model incorporates historical and current field characterization data up through Spring 1999. Model preprocessing is automated so that future updates and modifications can be performed quickly and efficiently. The CKLP regional reactor model can be used to guide characterization, perform scoping analyses of contaminant transport, and serve as a common base for subsequent finer-scale transport and remedial/feasibility models for each reactor area.
Flach, G.P.
Uncertainty Analysis Framework - Hanford Site-Wide Groundwater Flow and Transport Model
Pacific Northwest National Laboratory (PNNL) embarked on a new initiative to strengthen the technical defensibility of the predictions being made with a site-wide groundwater flow and transport model at the U.S. Department of Energy Hanford Site in southeastern Washington State. In FY 2000, the focus of the initiative was on the characterization of major uncertainties in the current conceptual model that would affect model predictions. The long-term goals of the initiative are the development and implementation of an uncertainty estimation methodology in future assessments and analyses using the site-wide model. This report focuses on the development and implementation of an uncertainty analysis framework.
Cole, Charles R.; Bergeron, Marcel P.; Murray, Christopher J.; Thorne, Paul D.; Wurstner, Signe K.; Rogers, Phillip M.
Numerical modeling of deep groundwater flow and heat transport in the Williston Basin
A numerical modeling approach has been used to evaluate quantitatively the effects of fluid flow on contemporary heat flow in an intracratonic basin. The authors have selected the Williston basin for this hydrodynamic study because of the opportunity it presents to assess the relation of deep groundwater flow to basin geothermics and the associated features of diagenesis and petroleum accumulation. The finite element method is used to solve the coupled equations of fluid flow and heat transport in two-dimensional sections of the basin. Both the fluid- and heat-flow regime are assumed to be at steady state, and the fluid flow is driven primarily by the water-table relief which is taken to be a subdued replica of land-surface topography. Buoyancy forces may also affect flow through fluid density gradients created by temperature and salinity effects. Three southwest-northwest oriented sections across the basin were modeled using available and estimated parameter data. The predicted flow patterns are most strongly affected by the topography, but the Devonian salt unit and Cretaceous shale unit exert some control. Cross-formational flow is especially important near the downdip, solution edge of the salt beds. Flow rates rarely exceed 0.5 m/year in the deep-central part of the basin, yet there does exist a marked effect on heat flow, albeit subdued by the blanket effect of the low-permeability Cretaceous shales. The regional effect of the topography-driven flow system is reflected in present-day salinity patterns and heat-flow data.
Garven, G.; Vigrass, L.
New approximation for free surface flow of groundwater: capillarity correction
capillarity correction for free surface groundwater flow as modelled by the Boussinesq equation is re; Shallow flow expansion; Simplified approximation 1. Introduction Groundwater heads in coastal aquifersNew approximation for free surface flow of groundwater: capillarity correction D.-S. Jeng a,*, B
Walter, M.Todd
Visualization of groundwater flow using line integral convolution
for the simulation of groundwater flow and transport models. INTRODUCTION Nowadays, 3D numerical simulationsVisualization of groundwater flow using line integral convolution J�?RG GOTTHARDT & CAROLA BL�?MER of groundwater flow and transport problems become more and more common. At the same time the need for adequate
Andrzejak, Artur
Groundwater flow and groundwater-stream interaction in fractured and dipping sedimentary rocks
detailed numerical models to evaluate the effects of various factors that influence groundwater flow. Introduction [2] The rate and direction of groundwater flow at a given location is driven by hydraulic gradient], where groundwater occurs in tilted, fractured beds. A simple con- ceptual model of the hydrogeology
Toran, Laura
Numerical Simulation of Inter-basin Groundwater Flow into Northern Yucca Flat, Nevada National Security Site, Using the Death Valley Regional Flow System Model
Models of groundwater flow for the Yucca Flat area of the Nevada National Security Site (NNSS) are under development by the U.S. Department of Energy (DOE) for corrective action investigations of the Yucca Flat-Climax Mine Corrective Action Unit (CAU). One important aspect of these models is the quantity of inter-basin groundwater flow from regional systems to the north. This component of flow, together with its uncertainty, must be properly accounted for in the CAU flow models to provide a defensible regional framework for calculations of radionuclide transport that will support determinations of the Yucca Flat-Climax Mine contaminant boundary. Because characterizing flow boundary conditions in northern Yucca Flat requires evaluation to a higher level of detail than the scale of the Yucca Flat-Climax Mine CAU model can efficiently provide, a study more focused on this aspect of the model was required.
Pohlmann Karl,Ye Ming
Coupled modeling of groundwater flow solute transport, chemical reactions and microbial processes in the 'SP' island
The Redox Zone Experiment was carried out at the Aespoe HRL in order to study the redox behavior and the hydrochemistry of an isolated vertical fracture zone disturbed by the excavation of an access tunnel. Overall results and interpretation of the Redox Zone Project were reported by /Banwart et al, 1995/. Later, /Banwart et al, 1999/ presented a summary of the hydrochemistry of the Redox Zone Experiment. Coupled groundwater flow and reactive transport models of this experiment were carried out by /Molinero, 2000/ who proposed a revised conceptual model for the hydrogeology of the Redox Zone Experiment which could explain simultaneously measured drawdown and salinity data. The numerical model was found useful to understand the natural system. Several conclusions were drawn about the redox conditions of recharge waters, cation exchange capacity of the fracture zone and the role of mineral phases such as pyrite, calcite, hematite and goethite. This model could reproduce the measured trends of dissolved species, except for bicarbonate and sulfate which are affected by microbially-mediated processes. In order to explore the role of microbial processes, a coupled numerical model has been constructed which accounts for water flow, reactive transport and microbial processes. The results of this model is presented in this report. This model accounts for groundwater flow and reactive transport in a manner similar to that of /Molinero, 2000/ and extends the preliminary microbial model of /Zhang, 2001/ by accounting for microbially-driven organic matter fermentation and organic matter oxidation. This updated microbial model considers simultaneously the fermentation of particulate organic matter by yeast and the oxidation of dissolved organic matter, a product of fermentation. Dissolved organic matter is produced by yeast and serves also as a substrate for iron-reducing bacteria. Model results reproduce the observed increase in bicarbonate and sulfate concentration, thus adding additional evidence for the possibility of organic matter oxidation as the main source of bicarbonate. Model results indicate that pH and Eh are relatively stable. The dissolution-precipitation trends of hematite, pyrite and calcite also coincide with those indicated by the conceptual model. A thorough sensitivity analysis has been performed for the most relevant microbial parameters as well as for initial and boundary POC and DOC concentrations. The results of such analysis indicate that computed concentrations of bicarbonate, sulfate and DOC are sensitive to most of the microbial parameters, including specific growth rates, half-saturation constants, proportionality coefficients and yield coefficients. Model results, however, are less sensitive to the yield coefficient of DOC to iron-reducer bacteria. The sensitivity analysis indicates that changes in fermentation microbial parameters affect the growth of the iron-reducer, thus confirming the interconnection of both microbial processes. Computed concentrations of bicarbonate and sulfate are found to be sensitive to changes in the initial concentration of POC and the boundary concentration of DOC, but they lack sensitivity to the initial concentration of DOC and the boundary concentration of POC. The explanation for such result is related to the fact that POC has a low mobility due to its large molecular weight. DOC, however, can migrate downwards. Although a coupled hydro-bio-geochemical 1-D model can reproduce the observed ''unexpected'' increase of concentrations of bicarbonate and sulfate at a depth of 70 m, further modeling work is required in order to obtain a similar conclusion under the more realistic two dimensional conditions of the fracture zone.
Samper, Javier; Molinero, Jorg; Changbing, Yang; Zhang, Guoxiang
Groundwater Modeling (Geological Sciences 16:460:528:01) Purpose: Learn to build a groundwater flow and transport model using Visual MODFLOW
and Groundwater Modeling, by Nevin Kresic Applied Groundwater Model, by Mary P. Anderson and William W. Woessner://envsci.rutgers.edu/~yreinfelder/GEOL_528/Anderson-Chapters.pdf Material: PC laptop (or Mac running Windows) If using lab computer, a flash Ingredients of Final Report Anderson Chapters 7.7, 7.8, 17, ASTMGuide Catch up on Project Catch
Regional groundwater flow and tritium transport modeling and risk assessment of the underground test area, Nevada Test Site, Nevada
The groundwater flow system of the Nevada Test Site and surrounding region was evaluated to estimate the highest potential current and near-term risk to the public and the environment from groundwater contamination downgradient of the underground nuclear testing areas. The highest, or greatest, potential risk is estimated by assuming that several unusually rapid transport pathways as well as public and environmental exposures all occur simultaneously. These conservative assumptions may cause risks to be significantly overestimated. However, such a deliberate, conservative approach ensures that public health and environmental risks are not underestimated and allows prioritization of future work to minimize potential risks. Historical underground nuclear testing activities, particularly detonations near or below the water table, have contaminated groundwater near testing locations with radioactive and nonradioactive constituents. Tritium was selected as the contaminant of primary concern for this phase of the project because it is abundant, highly mobile, and represents the most significant contributor to the potential radiation dose to humans for the short term. It was also assumed that the predicted risk to human health and the environment from tritium exposure would reasonably represent the risk from other, less mobile radionuclides within the same time frame. Other contaminants will be investigated at a later date. Existing and newly collected hydrogeologic data were compiled for a large area of southern Nevada and California, encompassing the Nevada Test Site regional groundwater flow system. These data were used to develop numerical groundwater flow and tritium transport models for use in the prediction of tritium concentrations at hypothetical human and ecological receptor locations for a 200-year time frame. A numerical, steady-state regional groundwater flow model was developed to serve as the basis for the prediction of the movement of tritium from the underground testing areas on a regional scale. The groundwater flow model was used in conjunction with a particle-tracking code to define the pathlines followed by groundwater particles originating from 415 points associated with 253 nuclear test locations. Three of the most rapid pathlines were selected for transport simulations. These pathlines are associated with three nuclear test locations, each representing one of the three largest testing areas. These testing locations are: BOURBON on Yucca Flat, HOUSTON on Central Pahute Mesa, and TYBO on Western Pahute Mesa. One-dimensional stochastic tritium transport simulations were performed for the three pathlines using the Monte Carlo method with Latin hypercube sampling. For the BOURBON and TYBO pathlines, sources of tritium from other tests located along the same pathline were included in the simulations. Sensitivity analyses were also performed on the transport model to evaluate the uncertainties associated with the geologic model, the rates of groundwater flow, the tritium source, and the transport parameters. Tritium concentration predictions were found to be mostly sensitive to the regional geology in controlling the horizontal and vertical position of transport pathways. The simulated concentrations are also sensitive to matrix diffusion, an important mechanism governing the migration of tritium in fractured carbonate and volcanic rocks. Source term concentration uncertainty is most important near the test locations and decreases in importance as the travel distance increases. The uncertainty on groundwater flow rates is as important as that on matrix diffusion at downgradient locations. The risk assessment was performed to provide conservative and bounding estimates of the potential risks to human health and the environment from tritium in groundwater. Risk models were designed by coupling scenario-specific tritium intake with tritium dose models and cancer and genetic risk estimates using the Monte Carlo method. Estimated radiation doses received by individuals from chronic exposure to tritium, and the corre
A CONVERGENT EXPLICIT GROUNDWATER MODEL Victor M. Ponce
A CONVERGENT EXPLICIT GROUNDWATER MODEL Victor M. Ponce Professor, Department of Civil Works, Ankara, Turkey. ABSTRACT: A groundwater model is developed by using an explicit formulation groundwater flow with excellent stability, convergence, and mass-conservation properties. 1 #12;INTRODUCTION
Ponce, V. Miguel
Regionally compartmented groundwater flow on Mars Keith P. Harrison1
the basis for such a test. Specifically, we use groundwater models to predict regions of cryosphere that groundwater flow was likely regionally compartmented. Furthermore, the consistent occurrence of modeled. Geophys. Res., 114, E04004, doi:10.1029/2008JE003300. 1. Introduction [2] Groundwater is thought to have
Harrison, Keith
A groundwater flow and transport model of long-term radionuclide migration in central Frenchman flat, Nevada test site
A set of groundwater flow and transport models were created for the Central Testing Area of Frenchman Flat at the former Nevada Test Site to investigate the long-term consequences of a radionuclide migration experiment that was done between 1975 and 1990. In this experiment, radionuclide migration was induced from a small nuclear test conducted below the water table by pumping a well 91 m away. After radionuclides arrived at the pumping well, the contaminated effluent was discharged to an unlined ditch leading to a playa where it was expected to evaporate. However, recent data from a well near the ditch and results from detailed models of the experiment by LLNL personnel have convincingly demonstrated that radionuclides from the ditch eventually reached the water table some 220 m below land surface. The models presented in this paper combine aspects of these detailed models with concepts of basin-scale flow to estimate the likely extent of contamination resulting from this experiment over the next 1,000 years. The models demonstrate that because regulatory limits for radionuclide concentrations are exceeded only by tritium and the half-life of tritium is relatively short (12.3 years), the maximum extent of contaminated groundwater has or will soon be reached, after which time the contaminated plume will begin to shrink because of radioactive decay. The models also show that past and future groundwater pumping from water supply wells within Frenchman Flat basin will have negligible effects on the extent of the plume.
Kwicklis, Edward Michael [Los Alamos National Laboratory; Becker, Naomi M [Los Alamos National Laboratory; Ruskauff, Gregory [NAVARRO-INTERA, LLC.; De Novio, Nicole [GOLDER AND ASSOC.; Wilborn, Bill [US DOE NNSA NSO
Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0
This report documents the analysis of the available hydrologic data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.
Drici, Warda
Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Units 101 and 102: Central and Western Pahute Mesa, Nye County, Nevada, Revision 0
This report documents the analysis of the available transport parameter data conducted in support of the development of a Corrective Action Unit (CAU) groundwater flow model for Central and Western Pahute Mesa: CAUs 101 and 102.
A Validation Process for the Groundwater Flow and Transport Model of the Faultless Nuclear Test at Central Nevada Test Area
Many sites of groundwater contamination rely heavily on complex numerical models of flow and transport to develop closure plans. This has created a need for tools and approaches that can be used to build confidence in model predictions and make it apparent to regulators, policy makers, and the public that these models are sufficient for decision making. This confidence building is a long-term iterative process and it is this process that should be termed ''model validation.'' Model validation is a process not an end result. That is, the process of model validation cannot always assure acceptable prediction or quality of the model. Rather, it provides safeguard against faulty models or inadequately developed and tested models. Therefore, development of a systematic approach for evaluating and validating subsurface predictive models and guiding field activities for data collection and long-term monitoring is strongly needed. This report presents a review of model validation studies that pertain to groundwater flow and transport modeling. Definitions, literature debates, previously proposed validation strategies, and conferences and symposia that focused on subsurface model validation are reviewed and discussed. The review is general in nature, but the focus of the discussion is on site-specific, predictive groundwater models that are used for making decisions regarding remediation activities and site closure. An attempt is made to compile most of the published studies on groundwater model validation and assemble what has been proposed or used for validating subsurface models. The aim is to provide a reasonable starting point to aid the development of the validation plan for the groundwater flow and transport model of the Faultless nuclear test conducted at the Central Nevada Test Area (CNTA). The review of previous studies on model validation shows that there does not exist a set of specific procedures and tests that can be easily adapted and applied to determine the validity of site-specific groundwater models. This is true for both deterministic and stochastic models, with the latter posing a more difficult and challenging problem when it comes to validation. This report then proposes a general validation approach for the CNTA model, which addresses some of the important issues recognized in previous validation studies, conferences, and symposia as crucial to the process. The proposed approach links model building, model calibration, model predictions, data collection, model evaluations, and model validation in an iterative loop. The approach focuses on use of collected validation data to reduce model uncertainty and narrow the range of possible outcomes of stochastic numerical models. It accounts for the stochastic nature of the numerical CNTA model, which used Monte Carlo simulation approach. The proposed methodology relies on the premise that absolute validity is not even a theoretical possibility and is not a regulatory requirement. Rather, it highlights the importance of testing as many aspects of the model as possible and using as many diverse statistical tools as possible for rigorous checking and confidence building in the model and its predictions. It is this confidence that will eventually allow for regulator and public acceptance of decisions based on the model predictions.
Ahmed Hassan
TYBO/BENHAM: Model Analysis of Groundwater Flow and Radionuclide Migration from Underground Nuclear Tests in Southwestern Pahute Mesa, Nevada
Recent field studies have led to the discovery of trace quantities of plutonium originating from the BENHAM underground nuclear test in two groundwater observation wells on Pahute Mesa at the Nevada Test Site. These observation wells are located 1.3 km from the BENHAM underground nuclear test and approximately 300 m from the TYBO underground nuclear test. In addition to plutonium, several other conservative (e.g. tritium) and reactive (e.g. cesium) radionuclides were found in both observation wells. The highest radionuclide concentrations were found in a well sampling a welded tuff aquifer more than 500m above the BENHAM emplacement depth. These measurements have prompted additional investigations to ascertain the mechanisms, processes, and conditions affecting subsurface radionuclide transport in Pahute Mesa groundwater. This report describes an integrated modeling approach used to simulate groundwater flow, radionuclide source release, and radionuclide transport near the BENHAM and TYBO underground nuclear tests on Pahute Mesa. The components of the model include a flow model at a scale large enough to encompass many wells for calibration, a source-term model capable of predicting radionuclide releases to aquifers following complex processes associated with nonisothermal flow and glass dissolution, and site-scale transport models that consider migration of solutes and colloids in fractured volcanic rock. Although multiple modeling components contribute to the methodology presented in this report, they are coupled and yield results consistent with laboratory and field observations. Additionally, sensitivity analyses are conducted to provide insight into the relative importance of uncertainty ranges in the transport parameters.
Andrew Wolfsberg; Lee Glascoe; Guoping Lu; Alyssa; Olson; Peter Lichtner; Maureen McGraw; Terry Cherry; ,; Guy Roemer
An Efficient Probabilistic Finite Element Method for Stochastic Groundwater Flow
of groundwater flow and transport from mathematical models involves considerable uncertainty due to the presenceAn Efficient Probabilistic Finite Element Method for Stochastic Groundwater Flow Harald Osnes Hans by nonlinear effects as oe Y approaches unity in more general domains. 1 #12; 1 Introduction The prediction
Osnes, Harald
Modeling of Groundwater Flow and Radionuclide Transport at the Climax Mine sub-CAU, Nevada Test Site
The Yucca Flat-Climax Mine Corrective Action Unit (CAU) on the Nevada Test Site comprises 747 underground nuclear detonations, all but three of which were conducted in alluvial, volcanic, and carbonate rocks in Yucca Flat. The remaining three tests were conducted in the very different hydrogeologic setting of the Climax Mine granite stock located in Area 15 at the northern end of Yucca Flat. As part of the Corrective Action Investigation (CAI) for the Yucca Flat-Climax Mine CAU, models of groundwater flow and radionuclide transport will be developed for Yucca Flat. However, two aspects of these CAU-scale models require focused modeling at the northern end of Yucca Flat beyond the capability of these large models. First, boundary conditions and boundary flows along the northern reaches of the Yucca Flat-Climax Mine CAU require evaluation to a higher level of detail than the CAU-scale Yucca Flat model can efficiently provide. Second, radionuclide fluxes from the Climax tests require analysis of flow and transport in fractured granite, a unique hydrologic environment as compared to Yucca Flat proper. This report describes the Climax Mine sub-CAU modeling studies conducted to address these issues, with the results providing a direct feed into the CAI for the Yucca Flat-Climax Mine CAU. Three underground nuclear detonations were conducted for weapons effects testing in the Climax stock between 1962 and 1966: Hard Hat, Pile Driver, and Tiny Tot. Though there is uncertainty regarding the position of the water table in the stock, it is likely that all three tests were conducted in the unsaturated zone. In the early 1980s, the Spent Fuel Test-Climax (SFT-C) was constructed to evaluate the feasibility of retrievable, deep geologic storage of commercial nuclear reactor wastes. Detailed mapping of fractures and faults carried out for the SFT-C studies greatly expanded earlier data sets collected in association with the nuclear tests and provided invaluable information for subsequent modeling studies at Climax. The objectives of the Climax Mine sub-CAU work are to (1) provide simulated heads and groundwater flows for the northern boundaries of the Yucca Flat-Climax Mine CAU model, while incorporating alternative conceptualizations of the hydrogeologic system with their associated uncertainty, and (2) provide radionuclide fluxes from the three tests in the Climax stock using modeling techniques that account for groundwater flow in fractured granite. Meeting these two objectives required two different model scales. The northern boundary groundwater fluxes were addressed using the Death Valley Regional Flow System (DVRFS) model (Belcher, 2004) developed by the U.S. Geological Survey as a modeling framework, with refined hydrostratigraphy in a zone north of Yucca Flat and including Climax stock. Radionuclide transport was simulated using a separate model confined to the granite stock itself, but linked to regional groundwater flow through boundary conditions and calibration targets.
K. Pohlmann; M. Ye; D. Reeves; M. Zavarin; D. Decker; J. Chapman
Three-dimensional numerical modeling of the influence of faults on groundwater flow at Yucca Mountain, Nevada
Numerical simulations of groundwater flow at Yucca Mountain, Nevada are used to investigate how the faulted hydrogeologic structure influences groundwater flow from a proposed high-level nuclear waste repository. Simulations are performed using a 3-D model that has a unique grid block discretization to accurately represent the faulted geologic units, which have variable thicknesses and orientations. Irregular grid blocks enable explicit representation of these features. Each hydrogeologic layer is discretized into a single layer of irregular and dipping grid blocks, and faults are discretized such that they are laterally continuous and displacement varies along strike. In addition, the presence of altered fault zones is explicitly modeled, as appropriate. The model has 23 layers and 11 faults, and approximately 57,000 grid blocks and 200,000 grid block connections. In the past, field measurement of upward vertical head gradients and high water table temperatures near faults were interpreted as indicators of upwelling from a deep carbonate aquifer. Simulations show, however, that these features can be readily explained by the geometry of hydrogeologic layers, the variability of layer permeabilities and thermal conductivities, and by the presence of permeable fault zones or faults with displacement only. In addition, a moderate water table gradient can result from fault displacement or a laterally continuous low permeability fault zone, but not from a high permeability fault zone, as others postulated earlier. Large-scale macrodispersion results from the vertical and lateral diversion of flow near the contact of high and low permeability layers at faults, and from upward flow within high permeability fault zones. Conversely, large-scale channeling can occur due to groundwater flow into areas with minimal fault displacement. Contaminants originating at the water table can flow in a direction significantly different than that of the water table gradient, and isolated zones of contaminants will occur at the water table downgradient. This behavior is not predicted by traditional models of contaminant transport. In addition, the influence of a particular type of fault cannot be generalized; depending on the location where contaminants enter the saturated zone, faults may either enhance of inhibit vertical dispersion.
Cohen, Andrew J.B.
Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, Rev. No.: 0
The Phase II Frenchman Flat groundwater flow model is a key element in the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996) corrective action strategy for the Underground Test Area (UGTA) Frenchman Flat corrective action unit (CAU). The objective of this integrated process is to provide an estimate of the vertical and horizontal extent of contaminant migration for each CAU to predict contaminant boundaries. A contaminant boundary is the model-predicted perimeter that defines the extent of radionuclide-contaminated groundwater from underground testing above background conditions exceeding the ''Safe Drinking Water Act'' (SDWA) standards. The contaminant boundary will be composed of both a perimeter boundary and a lower hydrostratigraphic unit (HSU) boundary. The computer model will predict the location of this boundary within 1,000 years and must do so at a 95 percent level of confidence. Additional results showing contaminant concentrations and the location of the contaminant boundary at selected times will also be presented. These times may include the verification period, the end of the five-year proof-of-concept period, as well as other times that are of specific interest. This report documents the development and implementation of the groundwater flow model for the Frenchman Flat CAU. Specific objectives of the Phase II Frenchman Flat flow model are to: (1) Incorporate pertinent information and lessons learned from the Phase I Frenchman Flat CAU models. (2) Develop a three-dimensional (3-D), mathematical flow model that incorporates the important physical features of the flow system and honors CAU-specific data and information. (3) Simulate the steady-state groundwater flow system to determine the direction and magnitude of groundwater fluxes based on calibration to Frenchman Flat hydrogeologic data. (4) Quantify the uncertainty in the direction and magnitude of groundwater flow due to uncertainty in parameter values and alternative component conceptual models (e.g., geology, boundary flux, and recharge).
John McCord
Validation, Proof-of-Concept, and Postaudit of the Groundwater Flow and Transport Model of the Project Shoal Area
The groundwater flow and radionuclide transport model characterizing the Shoal underground nuclear test has been accepted by the State of Nevada Division of Environmental Protection. According to the Federal Facility Agreement and Consent Order (FFACO) between DOE and the State of Nevada, the next steps in the closure process for the site are then model validation (or postaudit), the proof-of-concept, and the long-term monitoring stage. This report addresses the development of the validation strategy for the Shoal model, needed for preparing the subsurface Corrective Action Decision Document-Corrective Action Plan and the development of the proof-of-concept tools needed during the five-year monitoring/validation period. The approach builds on a previous model, but is adapted and modified to the site-specific conditions and challenges of the Shoal site.
Ground-water flow and transport modeling of the NRC-licensed waste disposal facility, West Valley, New York
This report describes a simulation study of groundwater flow and radionuclide transport from disposal at the NRC licensed waste disposal facility in West Valley, New York. A transient, precipitation driven, flow model of the near-surface fractured till layer and underlying unweathered till was developed and calibrated against observed inflow data into a recently constructed interceptor trench for the period March--May 1990. The results suggest that lateral flow through the upper, fractured till layer may be more significant than indicated by previous, steady state flow modeling studies. A conclusive assessment of the actual magnitude of lateral flow through the fractured till could however not be made. A primary factor contributing to this uncertainty is the unknown contribution of vertical infiltration through the interceptor trench cap to the total trench inflow. The second part of the investigation involved simulation of the migration of Sr-90, Cs-137 and Pu-239 from the one of the fuel hull disposal pits. A first-order radionuclide leach rate with rate coefficient of 10{sup {minus}6}/day was assumed to describe radionuclide release into the disposal pit. The simulations indicated that for wastes buried below the fractured till zone, no significant migration would occur. However, under the assumed conditions, significant lateral migration could occur for radionuclides present in the upper, fractured till zone. 23 refs., 68 figs., 12 tabs.
Kool, J.B.; Wu, Y.S. (HydroGeoLogic, Inc., Herndon, VA (United States))
A three-dimensional numerical model of predevelopment conditions in the Death Valley regional ground-water flow system, Nevada and California
In the early 1990's, two numerical models of the Death Valley regional ground-water flow system were developed by the U.S. Department of Energy. In general, the two models were based on the same basic hydrogeologic data set. In 1998, the U.S. Department of Energy requested that the U.S. Geological Survey develop and maintain a ground-water flow model of the Death Valley region in support of U.S. Department of Energy programs at the Nevada Test Site. The purpose of developing this ''second-generation'' regional model was to enhance the knowledge and understanding of the ground-water flow system as new information and tools are developed. The U.S. Geological Survey also was encouraged by the U.S. Department of Energy to cooperate to the fullest extent with other Federal, State, and local entities in the region to take advantage of the benefits of their knowledge and expertise. The short-term objective of the Death Valley regional ground-water flow system project was to develop a steady-stat e representation of the predevelopment conditions of the ground-water flow system utilizing the two geologic interpretations used to develop the previous numerical models. The long-term objective of this project was to construct and calibrate a transient model that simulates the ground-water conditions of the study area over the historical record that utilizes a newly interpreted hydrogeologic conceptual model. This report describes the result of the predevelopment steady-state model construction and calibration.
D'Agnese, F.A.; O'Brien, G.M.; Faunt, C.C.; Belcher, W.R.; San Juan, Carma
Simulation of salt migrations in density dependent groundwater flow
and uses a finite element method for the simulation of groundwater flow in the lateral (2D) direction (third dimension) a finite difference method is used in the simula- tions. Numerical experiments are done of this thesis is to investigate the possibilities of modelling salt migrations in density dependent groundwater
Vuik, Kees
Water Budget Analysis and Groundwater Inverse Modeling
the hydraulic conductivity field conditioned on the measurements of hydraulic conductivity and hydraulic head for saturated flow in randomly heterogeneous porous media. The groundwater modeling approach was found to be efficient in identifying the dominant...
Farid Marandi, Sayena
Modelling water flow and seasonal soil moisture dynamics in an alluvial groundwater-fed wetland Hydrology and Earth System Sciences, 7(1), 5766 (2003) EGU
Hydrology and Earth System Sciences, 7(1), 5766 (2003) © EGU Modelling water flow and seasonal soil between groundwater, surface water and climatic conditions. Knowledge of the hydrology of these systems tool to capture their hydrological complexity. In this study, a 2D-model describing saturated
Paris-Sud XI, Université de
Engineering Geology 52 (1999) 231250 Mathematical modelling of groundwater flow at Sellafield, UK
hydraulic head variations. Sensitivity analyses of geological variables showed that the rate of groundwater between the calculated equivalent freshwater head and that measured in situ, regardless of the hydraulic
Haszeldine, Stuart
Modeling Groundwater Flow and Transport of Radionuclides at Amchitka Island's Underground Nuclear Tests: Milrow, Long Shot, and Cannikin
Since 1963, all United States nuclear tests have been conducted underground. A consequence of this testing has been the deposition of large amounts of radioactive material in the subsurface, sometimes in direct contact with groundwater. The majority of this testing occurred on the Nevada Test Site (NTS), but a limited number of experiments were conducted in other locations. One of these locations, Amchitka Island, Alaska is the subject of this report. Three underground nuclear tests were conducted on Amchitka Island. Long Shot was an 80-kiloton-yield test conducted at a depth of 700 meters (m) on October 29, 1965 (DOE, 2000). Milrow had an announced yield of about 1,000 kilotons, and was detonated at a depth of 1,220 m on October 2, 1969. Cannikin had an announced yield less than 5,000 kilotons, and was conducted at a depth of 1,790 m on November 6, 1971. The purpose of this work is to provide a portion of the information needed to conduct a human-health risk assessment of the potential hazard posed by the three underground nuclear tests on Amchitka Island. Specifically, the focus of this work is the subsurface transport portion, including the release of radionuclides from the underground cavities and their movement through the groundwater system to the point where they seep out of the ocean floor and into the marine environment. This requires a conceptual model of groundwater flow on the island using geologic, hydrologic, and chemical information, a numerical model for groundwater flow, a conceptual model of contaminant release and transport properties from the nuclear test cavities, and a numerical model for contaminant transport. Needed for the risk assessment are estimates of the quantity of radionuclides (in terms of mass flux) from the underground tests on Amchitka that could discharge to the ocean, the time of possible discharge, and the location in terms of distance from shoreline. The radionuclide data presented here are all reported in terms of normalized masses to avoid presenting classified information. As only linear processes are modeled, the results can be readily scaled by the true classified masses for use in the risk assessment. The modeling timeframe for the risk assessment was set at 1,000 years, though some calculations are extended to 2,000 years. This first section of the report endeavors to orient the reader with the environment of Amchitka and the specifics of the underground nuclear tests. Of prime importance are the geologic and hydrologic conditions of the subsurface. A conceptual model for groundwater flow beneath the island is then developed and paired with an appropriate numerical modeling approach in section 2. The parameters needed for the model, supporting data for them, and data uncertainties are discussed at length. The calibration of the three flow models (one for each test) is then presented. At this point the conceptual radionuclide transport model is introduced and its numerical approach described in section 3. Again, the transport parameters and their supporting data and uncertainties are the focus. With all of the processes and parameters in place, the first major modeling phase can be discussed in section 4. In this phase, a parametric uncertainty analysis is performed to determine the sensitivity of the transport modeling results to the uncertainties present in the parameters. This analysis is motivated by the recognition of substantial uncertainty in the subsurface conditions on the island and the need to incorporate that uncertainty into the modeling. The conclusion of the first phase determines the parameters to hold as uncertain through the main flow and transport modeling. This second, main phase of modeling is presented in section 5, with the contaminant breakthrough behavior of each test site addressed. This is followed by a sensitivity analysis in section 6, regarding the importance of additional processes that could not be supported in the main modeling effort due to lack of data. Finally, the results for the individual sites are compared, the sensitivities discussed,
Ahmed Hassan; Karl Pohlmann; Jenny Chapman
Phase II Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0
This report documents pertinent hydrologic data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU): CAU 98. The purpose of this data compilation and related analyses is to provide the primary reference to support the development of the Phase II FF CAU groundwater flow model.
Groundwater flow and salt transport in a subterranean estuary2 driven by intensified wave conditions3
groundwater discharge, aquifer-ocean exchange, coastal45 aquifer, numerical modeling.46 #12;1. Introduction47 A numerical study, based on a density-dependent variably saturated groundwater flow model,26 was conducted1 Groundwater flow and salt transport in a subterranean estuary2 driven by intensified wave
Candea, George
Modeling the reactive inorganic solute distributions in the groundwater flow systems of the Hanford Site using inverse analytical modeling techniques.
??Inverse analytical techniques were used to model solute distributions and determine transport parameters for two flow systems in the Yakima Basalt subgroup at the Hanford� (more)
Adamski, Mark Robert
Flow calculations for Yucca Mountain groundwater travel time (GWTT-95)
In 1983, high-level radioactive waste repository performance requirements related to groundwater travel time were defined by NRC subsystem regulation 10 CFR 60.113. Although DOE is not presently attempting to demonstrate compliance with that regulation, understanding of the prevalence of fast paths in the groundwater flow system remains a critical element of any safety analyses for a potential repository system at Yucca Mountain, Nevada. Therefore, this analysis was performed to allow comparison of fast-path flow against the criteria set forth in the regulation. Models developed to describe the conditions for initiation, propagation, and sustainability of rapid groundwater movement in both the unsaturated and saturated zones will form part of the technical basis for total- system analyses to assess site viability and site licensability. One of the most significant findings is that the fastest travel times in both unsaturated and saturated zones are in the southern portion of the potential repository, so it is recommended that site characterization studies concentrate on this area. Results support the assumptions regarding the importance of an appropriate conceptual model of groundwater flow and the incorporation of heterogeneous material properties into the analyses. Groundwater travel times are sensitive to variation/uncertainty in hydrologic parameters and in infiltration flux at upper boundary of the problem domain. Simulated travel times are also sensitive to poorly constrained parameters of the interaction between flow in fractures and in the matrix.
Altman, S.J.; Arnold, B.W.; Barnard, R.W.; Barr, G.E.; Ho, C.K.; McKenna, S.A.; Eaton, R.R.
Spring temperatures in the Sagehen Basin, Sierra Nevada, CA: implications for heat flow and groundwater circulation
on groundwater flow depths within the basin. An analytical model based on these constraints email@example.com. Tel: +1 510 642 2288. Fax: +1 510 643 9980. Geofluids (2009) 9, 195207 INTRODUCTION Groundwater and groundwater circulation MARIA BRUMM, CHI-YUEN WANG AND MICHAEL MANGA Earth and Planetary Science, University
Manga, Michael
Modeling the reactive inorganic solute distributions in the groundwater flow systems of the Hanford Site using inverse analytical modeling techniques
Wallula Gap Row Sand Hallow Flows Sliver Fans Flo Ginkgo Flows Palause Falls Flow Vantage Intarbad Undifferent a e 0 s Rocky Coulee Flow Levering Flow Cohaeeet Row Unnamed Flow Birkett Flow Undifferentiated Flows McCoy Canyon Flow Unnamed... penetrate and have provided water samples for the flow systems in the Frenchman Springs and Rocky Coulee flows are: Ford, McGee, Enyeart, DB-11, RRL-2, DC-16, DC-19, DC-2, DB-15, DC-7, and DC-15. Based on the hydraulic data obtained from these wells...
ON THE RECOVERY OF TRANSPORT PARAMETERS IN GROUNDWATER MODELLING IAN KNOWLES AND AIMIN YAN. Introduction Saturated flow and single phase solute transport in confined ground- water systems are modelled one has to resort to indirect, or inverse, techniques to populate the model. In a groundwater system
Knowles, Ian W.
ON THE RECOVERY OF TRANSPORT PARAMETERS IN GROUNDWATER MODELLING IAN KNOWLES AND AIMIN YAN. Introduction Saturated flow and single phase solute transport in confined ground water systems are modelled to resort to indirect, or inverse, techniques to populate the model. In a groundwater system one
Geochemical and Isotopic Interpretations of Groundwater Flow in the Oasis Valley Flow System, Southern Nevada
This report summarizes the findings of a geochemical investigation of the Pahute Mesa-Oasis Valley groundwater flow system in southwestern Nevada. It is intended to provide geochemical data and interpretations in support of flow and contaminant transport modeling for the Western and Central Pahute Mesa Corrective Action Units.
J.M. Thomas; F.C. Benedict, Jr.; T.P. Rose; R.L. Hershey; J.B. Paces; Z.E. Peterman; I.M. Farnham; K.H. Johannesson; A.K. Singh; K.J. Stetzenbach; G.B. Hudson; J.M. Kenneally; G.F. Eaton; D.K. Smith
CONTINUOUSTIME FINITE ELEMENT ANALYSIS OF MULTIPHASE FLOW IN GROUNDWATER HYDROLOGY Zhangxin Chenwater system in groundwater hydrology is given. The system is written in a fractional flow formulation, i for an airwater system in groundwater hydrology, ff = a; w [1], [11], [26]: @(OEae ff s ff ) @t +r \\Delta
Impact of horizontal groundwater flow and localized deforestation on the development of shallow
Impact of horizontal groundwater flow and localized deforestation on the development of shallow that develop in the shallow subsurface as a result of localized deforestation in combination with shallow horizontal groundwater flow. Model results show how a patch-wise pattern of deforestation at the surface
Bense, Victor
03/29/02 McKenna, Eliassi, Inaba and Saegusa 1 Steady-State Groundwater Flow Modeling of the MIU Site Area
Laboratories, Albuquerque, New Mexico, USA 2 Japan Nuclear Cycle Development Institute Abstract Sandia National Department of Energy under contract DE-AC04-94-AL- 85000 For submission to: Symposium on Groundwater Flow
A Hydrostrat Model and Alternatives for Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainer Mesa-Shoshone Mountain, Nye County, Nevada
The three-dimensional hydrostratigraphic framework model for the Rainier Mesa-Shoshone Mountain Corrective Action Unit was completed in Fiscal Year 2006. The model extends from eastern Pahute Mesa in the north to Mid Valley in the south and centers on the former nuclear testing areas at Rainier Mesa, Aqueduct Mesa, and Shoshone Mountain. The model area also includes an overlap with the existing Underground Test Area Corrective Action Unit models for Yucca Flat and Pahute Mesa. The model area is geologically diverse and includes un-extended yet highly deformed Paleozoic terrain and high volcanic mesas between the Yucca Flat extensional basin on the east and caldera complexes of the Southwestern Nevada Volcanic Field on the west. The area also includes a hydrologic divide between two groundwater sub-basins of the Death Valley regional flow system. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the model area. Three deep characterization wells, a magnetotelluric survey, and reprocessed gravity data were acquired specifically for this modeling initiative. These data and associated interpretive products were integrated using EarthVision{reg_sign} software to develop the three-dimensional hydrostratigraphic framework model. Crucial steps in the model building process included establishing a fault model, developing a hydrostratigraphic scheme, compiling a drill-hole database, and constructing detailed geologic and hydrostratigraphic cross sections and subsurface maps. The more than 100 stratigraphic units in the model area were grouped into 43 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the volcanic units in the model area into 35 hydrostratigraphic units that include 16 aquifers, 12 confining units, 2 composite units (a mixture of aquifer and confining units), and 5 intrusive confining units. The underlying pre-Tertiary rocks are divided into six hydrostratigraphic units, including three aquifers and three confining units. Other units include an alluvial aquifer and a Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units ('layers' in the model). The model also incorporates 56 Tertiary normal faults and 4 Mesozoic thrust faults. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Four of these alternatives were developed so they can be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area Subproject of the Environmental Restoration Project.
NSTec Geotechnical Sciences Group
A Hydrostratigraphic System for Modeling Groundwater Flow and Radionuclide Migration at the Corrective Action Unit Scale, Nevada Test Site and Surrounding Areas, Clark, Lincoln, and Nye Counties, Nevada
Underground Test Area (UGTA) corrective action unit (CAU) groundwater flow and contaminant transport models of the Nevada Test Site (NTS) and vicinity are built upon hydrostratigraphic framework models (HFMs) that utilize the hydrostratigraphic unit (HSU) as the fundamental modeling component. The delineation and three-dimensional (3-D) modeling of HSUs within the highly complex geologic terrain that is the NTS requires a hydrostratigraphic system that is internally consistent, yet flexible enough to account for overlapping model areas, varied geologic terrain, and the development of multiple alternative HFMs. The UGTA CAU-scale hydrostratigraphic system builds on more than 50 years of geologic and hydrologic work in the NTS region. It includes 76 HSUs developed from nearly 300 stratigraphic units that span more than 570 million years of geologic time, and includes rock units as diverse as marine carbonate and siliciclastic rocks, granitic intrusives, rhyolitic lavas and ash-flow tuffs, and alluvial valley-fill deposits. The UGTA CAU-scale hydrostratigraphic system uses a geology-based approach and two-level classification scheme. The first, or lowest, level of the hydrostratigraphic system is the hydrogeologic unit (HGU). Rocks in a model area are first classified as one of ten HGUs based on the rock�s ability to transmit groundwater (i.e., nature of their porosity and permeability), which at the NTS is mainly a function of the rock�s primary lithology, type and degree of postdepositional alteration, and propensity to fracture. The second, or highest, level within the UGTA CAU-scale hydrostratigraphic system is the HSU, which is the fundamental mapping/modeling unit within UGTA CAU-scale HFMs. HSUs are 3-D bodies that are represented in the finite element mesh for the UGTA groundwater modeling process. HSUs are defined systematically by stratigraphically organizing HGUs of similar character into larger HSUs designations. The careful integration of stratigraphic information in the development of HSUs is important to assure individual HSUs are internally consistent, correlatable, and mappable throughout all the model areas.
Lance Prothro, Sigmund Drellack Jr., Jennifer Mercadante
Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1
This document presents a summary and framework of the available hydrologic data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater flow models. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.
Nathan Bryant
Sensitivity analysis of two-dimensional steady-state aquifer ow equations. Implications for groundwater ow model calibration
sensitivity, model calibration, well network design, groundwater flow modelling 1. Introduction Sensitivity for groundwater ow model calibration and validation N. Mazzillia, , V. Guinota , H. Jourdea a for two-dimensional groundwater flow model calibration and monitoring network design. Since the first step
Phase I Hydrologic Data for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nye County, Nevada, Rev. No.: 0
The U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) initiated the Underground Test Area (UGTA) Project to assess and evaluate the effects of the underground nuclear weapons tests on groundwater beneath the Nevada Test Site (NTS) and vicinity. The framework for this evaluation is provided in Appendix VI, Revision No. 1 (December 7, 2000) of the Federal Facility Agreement and Consent Order (FFACO, 1996). Section 3.0 of Appendix VI ''Corrective Action Strategy'' of the FFACO describes the process that will be used to complete corrective actions specifically for the UGTA Project. The objective of the UGTA corrective action strategy is to define contaminant boundaries for each UGTA corrective action unit (CAU) where groundwater may have become contaminated from the underground nuclear weapons tests. The contaminant boundaries are determined based on modeling of groundwater flow and contaminant transport. A summary of the FFACO corrective action process and the UGTA corrective action strategy is provided in Section 1.5. The FFACO (1996) corrective action process for the Yucca Flat/Climax Mine CAU 97 was initiated with the Corrective Action Investigation Plan (CAIP) (DOE/NV, 2000a). The CAIP included a review of existing data on the CAU and proposed a set of data collection activities to collect additional characterization data. These recommendations were based on a value of information analysis (VOIA) (IT, 1999), which evaluated the value of different possible data collection activities, with respect to reduction in uncertainty of the contaminant boundary, through simplified transport modeling. The Yucca Flat/Climax Mine CAIP identifies a three-step model development process to evaluate the impact of underground nuclear testing on groundwater to determine a contaminant boundary (DOE/NV, 2000a). The three steps are as follows: (1) Data compilation and analysis that provides the necessary modeling data that is completed in two parts: the first addressing the groundwater flow model, and the second the transport model. (2) Development of a groundwater flow model. (3) Development of a groundwater transport model. This report presents the results of the first part of the first step, documenting the data compilation, evaluation, and analysis for the groundwater flow model. The second part, documentation of transport model data will be the subject of a separate report. The purpose of this document is to present the compilation and evaluation of the available hydrologic data and information relevant to the development of the Yucca Flat/Climax Mine CAU groundwater flow model, which is a fundamental tool in the prediction of the extent of contaminant migration. Where appropriate, data and information documented elsewhere are summarized with reference to the complete documentation. The specific task objectives for hydrologic data documentation are as follows: (1) Identify and compile available hydrologic data and supporting information required to develop and validate the groundwater flow model for the Yucca Flat/Climax Mine CAU. (2) Assess the quality of the data and associated documentation, and assign qualifiers to denote levels of quality. (3) Analyze the data to derive expected values or spatial distributions and estimates of the associated uncertainty and variability.
Groundwater availability and flow processes in the Williston and Powder River basins in the Northern Great Plains
Groundwater availability and flow processes in the Williston and Powder River basins, OK The recent oil and gas development in the Williston structural basin (containing the Bakken will be used to develop inputs to a numerical model of groundwater flow in the Williston structural basin
Torgersen, Christian
1 INTRODUCTION The modular finitedifference groundwater flow
1 INTRODUCTION The modular finitedifference groundwater flow model (MODFLOW) developed by the U implemented as part of the U.S. Geological Survey (USGS) MODFLOW/MOC3D groundwater modeling package. The USGSdimensional groundwater systems (McDonald & Harbaugh, 1988, Harbaugh & McDonald, 1996). MOC3D is a solute
Russell, Thomas F.
Identification and Control Problems in Petroleum and Groundwater Modeling \\Lambda
Identification and Control Problems in Petroleum and Groundwater Modeling \\Lambda R.E. Ewing, y , M.S. Pilant, y J.G. Wade, z and A.T. Watson x Abstract The petroleum industry has wellestablished partial differential equation models for multiphase fluid flow through porous media, but the use of control
Ewing, Richard E.
Resolving discrepancies between hydraulic and chemical calibration data for seawater intrusion groundwater flow models by considering climate-driven sea level change.
Groundwater models of seawater intrusion environments can be calibrated using both hydraulic and chemical information. The possible impact of the long-term transient process of sea level change is difficult to identify, but important to accurate simulation of present conditions. The response times of the pressure and chemical fields to major fluctuations in sea level change are investigated
J. Chapman; A. Hassan; K. Pohlmann
Addendum for the Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, NevadaTest Site, Nye County, Nevada, Revision 0 (page changes)
This document, which makes changes to Phase II Groundwater Flow Model of Corrective Action Unit 98: Frenchman Flat, Nevada Test Site, Nye County, Nevada, S-N/99205--074, Revision 0 (May 2006) was prepared to address review comments on this final document provided by the Nevada Division of Environmental Protection (NDEP) in a letter dated June 20, 2006. The document includes revised pages that address NDEP review comments and comments from other document users. Change bars are included on these pages to identify where the text was revised. In addition to the revised pages, the following clarifications are made: � Section 6.0 Conceptual Model Uncertainty Analyses. Please note that in this section figures showing the observed versus simulated well head (Figures 6-1, 6-5, 6-7, 6-16, 6-28, 6-30, 6-32, 6-34, 6-37, 6-42, 6-47, 6-52, 6-57, 6-62, 6-71, and 6-86) have a vertical break in scale on the y axis. � Section 7.0 Parameter Sensitivity Analysis. In Section 7.2, the parameter perturbation analysis defines two components of the objective function PHI. These two components include the WELL component that represents the head portion of the objective function as measured in wells and the FLUX component that represents the lateral boundary flux portion of the objective function. In the text and figures in Section 7.2, the phrases �well portion of the objective function� and �head portion of the objective function� are used interchangeably in discussions of the WELL component of the objective function.
Development of one-dimensional computational fluid dynamics code 'GFLOW' for groundwater flow and contaminant transport analysis
Prediction of groundwater movement and contaminant transport in soil is an important problem in many branches of science and engineering. This includes groundwater hydrology, environmental engineering, soil science, agricultural engineering and also nuclear engineering. Specifically, in nuclear engineering it is applicable in the design of spent fuel storage pools and waste management sites in the nuclear power plants. Ground water modeling involves the simulation of flow and contaminant transport by groundwater flow. In the context of contaminated soil and groundwater system, numerical simulations are typically used to demonstrate compliance with regulatory standard. A one-dimensional Computational Fluid Dynamics code GFLOW had been developed based on the Finite Difference Method for simulating groundwater flow and contaminant transport through saturated and unsaturated soil. The code is validated with the analytical model and the benchmarking cases available in the literature. (authors)
Rahatgaonkar, P. S.; Datta, D.; Malhotra, P. K.; Ghadge, S. G. [Nuclear Power Corporation of India Ltd., R-2, Ent. Block, Nabhikiya Urja Bhavan, Anushakti Nagar, Mumbai - 400 094 (India)
AN AGGREGATIONBASED DOMAIN DECOMPOSITION PRECONDITIONER FOR GROUNDWATER FLOW \\Lambda
the standard finite element framework from [18,24]. The preconditioner also works well in the context of finiteAN AGGREGATIONBASED DOMAIN DECOMPOSITION PRECONDITIONER FOR GROUNDWATER FLOW \\Lambda E. W. JENKINS analysis of a twolevel additive Schwarz method in which the coarse mesh basis is constructed
Application of the discontinuous spectral Galerkin method to groundwater flow
method uses a finite-element discretization of the groundwater flow domain with basis functions with a standard finite-element method and a mixed finite-element method. Numerical sim- ulations show that the discontinuous spectral Galerkin approximation is more efficient than the standard finite-element method (in
Fagherazzi, Sergio
. Our analysis uses the standard finite element framework from [18,24]. The preconditioner also works well in the context of finite differences, however, as some of the examples in £ 3 illustrateAN AGGREGATION-BASED DOMAIN DECOMPOSITION PRECONDITIONER FOR GROUNDWATER FLOW E. W. JENKINS ¡, C
CE 473/573 Groundwater Course information
. Groundwater modeling 4.1. Introduction to finite-difference models 4.2. Models of groundwater flow 4.3. ModelsCE 473/573 Groundwater Fall 2011 Course information Instructor: Prof. Chris Rehmann rehmann of water and contaminants in groundwater systems to solve problems of groundwater resource evaluation
Rehmann, Chris
Error Control of Iterative Linear Solvers for Integrated Groundwater Models
and presentation of GMRES performance benchmarking results. Introduction As the groundwater model infrastructureError Control of Iterative Linear Solvers for Integrated Groundwater Models by Matthew F. Dixon1 for integrated groundwater models, which are implicitly coupled to another model, such as surface water models
Bai, Zhaojun
Dolomitization by ground-water flow systems in carbonate platforms
Dolomite occurs throughout the subsurface of modern carbonate platforms such as the Bahamas. Groundwater flow systems must be responsible for delivery of reactants needed for dolomitization. Reflux, freshwater lens flows, and thermal convection are large-scale flow systems that may be widespread in active platforms. The author has evaluated some aspects of the dynamics and characteristics of these processes with ground-water flow theory and by scaled sandbox experiments. Reflux is not restricted to hypersaline brines, but can occur with bankwaters of only slightly elevated salinity such as those found on the Bahama Banks today (42%). The lack of evaporites in a stratigraphic section, therefore, does not rule out the possibility that reflux may have operated. Flows associated with freshwater lenses include flow in the lens, in the mixing zone, and in the seawater beneath and offshore of the lens. Upward transfer of seawater through the platform margins occurs when surrounding cold ocean water migrates into the platform and is heated. This type of thermal convection (Kohout convection) has been studied by Francis Kohout in south Florida. The ranges of mass flux of magnesium in these processes are all comparable and are all sufficient to account for young dolomites beneath modern platforms. Each process yields dolomitized zones of characteristic shape and location and perhaps may be distinguishable in ancient rocks. The concepts presented here may have application to exploration for dolomite reservoirs in the Gulf Coast and elsewhere.
Simms, M.
on grand challenge problems. In today's petroleum industry, reservoir simulators are routinely usedPARAMETER ESTIMATION IN PETROLEUM AND GROUNDWATER MODELING R.E. Ewing, M.S. Pilant, J.G. Wade in the model, the numerical discretization used, and the solution algorithms employed. Parameter identification
Influence of faults on groundwater flow and transport at YuccaMountain, Nevada
Numerical simulations of groundwater flow at Yucca Mountain, Nevada are used to investigate how faults influence groundwater flow pathways and regional-scale macrodispersion. The 3-D model has a unique grid block discretization that facilitates the accurate representation of the complex geologic structure present in faulted formations. Each hydrogeologic layer is discretized into a single layer of irregular and dipping grid blocks, and faults are discretized such that they are laterally continuous and varied in displacement varies along strike. In addition, the presence of altered fault zones is explicitly modeled, as appropriate. Simulations show that upward head gradients can be readily explained by the geometry of hydrogeologic layers, the variability of layer permeabilities, and the presence of permeable fault zones or faults with displacement only, not necessarily by upwelling from a deep aquifer. Large-scale macrodispersion results from the vertical and lateral diversion of flow near the contact of high- and low-permeability layers at faults, and from upward flow within high-permeability fault zones. Conversely, large-scale channeling can occur as a result of groundwater flow into areas with minimal fault displacement. Contaminants originating at the water table can flow in a direction significantly different from that of the water table gradient, and isolated zones of contaminants can occur at the water table downgradient. By conducting both 2-D and 3-D simulations, we show that the 2-D cross-sectional models traditionally used to examine flow in faulted formations may not be appropriate. In addition, the influence of a particular type of fault cannot be generalized; depending on the location where contaminants enter the saturated zone, faults may either enhance or inhibit vertical dispersion.
Cohen, Andrew J.B.; Sitar, Nicholas
Heat Transport in Groundwater Systems--Finite Element Model
into groundwater aquifers for long term energy storage. Analytical solutions are available that predict water temperatures as hot water is injected into a groundwater aquifer, but little field and laboratory data are available to verify these models. The objectives...
Grubaugh, E. K.; Reddell, D. L.
Modeling and assessment of flow and transport in the Hueco Bolson, a transboundary groundwater system: the El Paso / Cuidad Juarez case
. Additionally, historical, current, and future stresses on the Hueco Bolson alluvial aquifer in the El Paso/Ciudad Juarez area due to excessive groundwater withdrawal can affect contaminant migration in the area. In the current study, an updated and improved...
Nwaneshiudu, Okechukwu
Groundwater Remediation Strategy Using Global Optimization Algorithms
as decision variables. Groundwater flow and particle-tracking models MODFLOW and MODPATH and a GO tool GLOBE; Algorithms; Ground-water management. Introduction The contamination of groundwater is a widespread problem, the simulation is carried out with available groundwater models for flow and transport, and the op- timization
Neumaier, Arnold
A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada
A new three-dimensional hydrostratigraphic framework model for the Yucca Flat-Climax Mine Corrective Action Unit was completed in 2005. The model area includes Yucca Flat and Climax Mine, former nuclear testing areas at the Nevada Test Site, and proximal areas. The model area is approximately 1,250 square kilometers in size and is geologically complex. Yucca Flat is a topographically closed basin typical of many valleys in the Basin and Range province. Faulted and tilted blocks of Tertiary-age volcanic rocks and underlying Proterozoic and Paleozoic sedimentary rocks form low ranges around the structural basin. During the Cretaceous Period a granitic intrusive was emplaced at the north end of Yucca Flat. A diverse set of geological and geophysical data collected over the past 50 years was used to develop a structural model and hydrostratigraphic system for the basin. These were integrated using EarthVision? software to develop the 3-dimensional hydrostratigraphic framework model. Fifty-six stratigraphic units in the model area were grouped into 25 hydrostratigraphic units based on each unit's propensity toward aquifer or aquitard characteristics. The authors organized the alluvial section into 3 hydrostratigraphic units including 2 aquifers and 1 confining unit. The volcanic units in the model area are organized into 13 hydrostratigraphic units that include 8 aquifers and 5 confining units. The underlying pre-Tertiary rocks are divided into 7 hydrostratigraphic units, including 3 aquifers and 4 confining units. Other units include 1 Tertiary-age sedimentary confining unit and 1 Mesozoic-age granitic confining unit. The model depicts the thickness, extent, and geometric relationships of these hydrostratigraphic units (''layers'' in the model) along with the major structural features (i.e., faults). The model incorporates 178 high-angle normal faults of Tertiary age and 2 low-angle thrust faults of Mesozoic age. The complexity of the model area and the non-uniqueness of some of the interpretations incorporated into the base model made it necessary to formulate alternative interpretations for some of the major features in the model. Five of these alternatives were developed so they could be modeled in the same fashion as the base model. This work was done for the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office in support of the Underground Test Area subproject of the Environmental Restoration Project.
Geotechnical Sciences Group Bechtel Nevada
Groundwater Impacts of Radioactive Wastes and Associated Environmental Modeling Assessment
This article provides a review of the major sources of radioactive wastes and their impacts on groundwater contamination. The review discusses the major biogeochemical processes that control the transport and fate of radionuclide contaminants in groundwater, and describe the evolution of mathematical models designed to simulate and assess the transport and transformation of radionuclides in groundwater.
Ma, Rui; Zheng, Chunmiao; Liu, Chongxuan
A Hydrostratigraphic Framework Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Clark, Lincoln and Nye Counties, Nevada
A new, revised three-dimensional (3-D) hydrostratigraphic framework model for Frenchman Flat was completed in 2004. The area of interest includes Frenchman Flat, a former nuclear testing area at the Nevada Test Site, and proximal areas. Internal and external reviews of an earlier (Phase I) Frenchman Flat model recommended additional data collection to address uncertainties. Subsequently, additional data were collected for this Phase II initiative, including five new drill holes and a 3-D seismic survey.
Bechtel Nevada
Experimental study of turbulent unconfined groundwater flow in a single fracture
Experimental study of turbulent unconfined groundwater flow in a single fracture Jiazhong Qiana groundwater flow in a single fracture under the conditions of different surface roughness and apertures. We found that the gradient of the Reynolds number versus the average velocity in a single fracture
Zhan, Hongbin
Modeling to Support Groundwater Contaminant Boundaries for the Shoal Underground Nuclear Test
Groundwater flow and radionuclide transport at the Shoal underground nuclear test are characterized using three-dimensional numerical models, based on site-specific hydrologic data. The objective of this modeling is to provide the flow and transport models needed to develop a contaminant boundary defining the extent of radionuclide-contaminated groundwater at the site throughout 1,000 years at a prescribed level of confidence. This boundary will then be used to manage the Project Shoal Area for the protection of the public and the environment.
K. Pohlmann; G. Pohll; J. Chapman; A. Hassan; R. Carroll; C. Shirley
The Development of a Coordinated Database for Water Resources and Flow Model in the Paso Del Norte Watershed
AND ASSOCIATED MODELS DEVELOPED FOR THE PASO DEL NORTE WATERSHED MODFLOW � MODULAR Three-Dimensional Finite-Difference Groundwater FLOW Model MODFLOW is a modular, three-dimensional, finite-difference, groundwater flow model that numerically solves... the three-dimensional groundwater flow equation for a porous medium by using a finite-difference method (Harbaugh et al. 2000; McDonald and Harbaugh 1988). MODFLOW simulates steady and transient (nonsteady) flow in an irregularly shaped flow system...
Sheng, Zhuping; Tillery, Sue; King, Phillip J.; Creel, Bobby; Brown, Christopher; Michelsen, Ari; Srinivasan, Raghavan; Granados, Alfredo
Spatial Models for Groundwater Behavioral Analysis in Regions of Maharashtra
Spatial Models for Groundwater Behavioral Analysis in Regions of Maharashtra M.Tech Dissertation on groundwater and classified the years into good year if water levels are above the seasonal model in that year such as land-use, local hydrogeology. #12;Contents 1 Introduction 1 1.1 Spatial Models
Sohoni, Milind
RAFT: A simulator for ReActive Flow and Transport of groundwater contaminants
This report documents the use of the simulator RAFT for the ReActive flow and Transport of groundwater contaminants. RAFT can be used as a predictive tool in the design and analysis of laboratory and field experiments or it can be used for the estimation of model/process parameters from experiments. RAFT simulates the reactive transport of groundwater contaminants in one, two-, or three-dimensions and it can model user specified source/link configurations and arbitrary injection strategies. A suite of solvers for transport, reactions and regression are employed so that a combination of numerical methods best suited for a problem can be chosen. User specified coupled equilibrium and kinetic reaction systems can be incorporated into RAFT. RAFT is integrated with a symbolic computational language MAPLE, to automate code generation for arbitrary reaction systems. RAFT is expected to be used as a simulator for engineering design for field experiments in groundwater remediation including bioremediation, reactive barriers and redox manipulation. As an integrated tool with both the predictive ability and the ability to analyze experimental data, RAFT can help in the development of remediation technologies, from laboratory to field.
Chilakapati, A.
Unsaturated Groundwater Flow Beneath Upper Mortandad Canyon, Los Alamos, New Mexico
Mortandad Canyon is a discharge site for treated industrial effluents containing radionuclides and other chemicals at Los Alamos National Laboratory, New Mexico. This study was conducted to develop an understanding of the unsaturated hydrologic behavior below the canyon floor. The main goal of this study was to evaluate the hypothetical performance of the vadose zone above the water table. Numerical simulations of unsaturated groundwater flow at the site were conducted using the Finite Element Heat and Mass Transfer (FEHM) code. A two-dimensional cross-section along the canyon's axis was used to model flow between an alluvial groundwater system and the regional aquifer approximately 300 m below. Using recharge estimated from a water budget developed in 1967, the simulations showed waters from the perched water table reaching the regional aquifer in 13.8 years, much faster than previously thought. Additionally, simulations indicate that saturation is occurring in the Guaje pumice bed an d that the Tshirege Unit 1B is near saturation. Lithologic boundaries between the eight materials play an important role in flow and solute transport within the system. Horizontal flow is shown to occur in three thin zones above capillary barriers; however, vertical flow dominates the system. Other simulations were conducted to examine the effects of changing system parameters such as varying recharge inputs, varying the distribution of recharge, and bypassing fast-path fractured basalt of uncertain extent and properties. System sensitivity was also explored by changing model parameters with respect to size and types of grids and domains, and the presence of dipping stratigraphy.
Dander, D.C.
The purpose of the saturated zone (SZ) flow and transport model abstraction task is to provide radionuclide-transport simulation results for use in the total system performance assessment (TSPA) for license application (LA) calculations. This task includes assessment of uncertainty in parameters that pertain to both groundwater flow and radionuclide transport in the models used for this purpose. This model report documents the following: (1) The SZ transport abstraction model, which consists of a set of radionuclide breakthrough curves at the accessible environment for use in the TSPA-LA simulations of radionuclide releases into the biosphere. These radionuclide breakthrough curves contain information on radionuclide-transport times through the SZ. (2) The SZ one-dimensional (I-D) transport model, which is incorporated in the TSPA-LA model to simulate the transport, decay, and ingrowth of radionuclide decay chains in the SZ. (3) The analysis of uncertainty in groundwater-flow and radionuclide-transport input parameters for the SZ transport abstraction model and the SZ 1-D transport model. (4) The analysis of the background concentration of alpha-emitting species in the groundwater of the SZ.
The purpose of this work is to characterize groundwater flow and contaminant transport at the Shoal underground nuclear test through numerical modeling using site-specific hydrologic data. The ultimate objective is the development of a contaminant boundary, a model-predicted perimeter defining the extent of radionuclide-contaminated groundwater from the underground test throughout 1,000 years at a prescribed level of confidence. This boundary will be developed using the numerical models described here, after they are approved for that purpose by DOE and NDEP.
Evaluation of groundwater flow and transport at the Shoal underground nuclear test: An interim report
Since 1962, all United States nuclear tests have been conducted underground. A consequence of this testing has been the deposition of large amounts of radioactive materials in the subsurface, sometimes in direct contact with groundwater. The majority of this testing occurred on the Nevada Test Site, but a limited number of experiments were conducted in other locations. One of these is the subject of this report, the Project Shoal Area (PSA), located about 50 km southeast of Fallon, Nevada. The Shoal test consisted of a 12-kiloton-yield nuclear detonation which occurred on October 26, 1963. Project Shoal was part of studies to enhance seismic detection of underground nuclear tests, in particular, in active earthquake areas. Characterization of groundwater contamination at the Project Shoal Area is being conducted by the US Department of Energy (DOE) under the Federal Facility Agreement and Consent Order (FFACO) with the State of Nevada Department of Environmental Protection and the US Department of Defense (DOD). This order prescribes a Corrective Action Strategy (Appendix VI), which, as applied to underground nuclear tests, involves preparing a Corrective Action Investigation Plan (CAIP), Corrective Action Decision Document (CADD), Corrective Action Plan, and Closure Report. The scope of the CAIP is flow and transport modeling to establish contaminant boundaries that are protective of human health and the environment. This interim report describes the current status of the flow and transport modeling for the PSA.
Pohll, G.; Chapman, J.; Hassan, A.; Papelis, C.; Andricevic, R.; Shirley, C.
Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nye County, Nevada, Revision 1
This document presents a summary and framework of available transport data and other information directly relevant to the development of the Rainier Mesa/Shoshone Mountain (RMSM) Corrective Action Unit (CAU) 99 groundwater transport model. Where appropriate, data and information documented elsewhere are briefly summarized with reference to the complete documentation.
Determining flow, recharge, and vadose zonedrainage in anunconfined aquifer from groundwater strontium isotope measurements, PascoBasin, WA
Strontium isotope compositions (87Sr/86Sr) measured in groundwater samples from 273 wells in the Pasco Basin unconfined aquifer below the Hanford Site show large and systematic variations that provide constraints on groundwater recharge, weathering rates of the aquifer host rocks, communication between unconfined and deeper confined aquifers, and vadose zone-groundwater interaction. The impact of millions of cubic meters of wastewater discharged to the vadose zone (103-105 times higher than ambient drainage) shows up strikingly on maps of groundwater 87Sr/86Sr. Extensive access through the many groundwater monitoring wells at the site allows for an unprecedented opportunity to evaluate the strontium geochemistry of a major aquifer, hosted primarily in unconsolidated sediments, and relate it to both long term properties and recent disturbances. Groundwater 87Sr/86Sr increases systematically from 0.707 to 0.712 from west to east across the Hanford Site, in the general direction of groundwater flow, as a result of addition of Sr from the weathering of aquifer sediments and from diffuse drainage through the vadose zone. The lower 87Sr/86Sr groundwater reflects recharge waters that have acquired Sr from Columbia River Basalts. Based on a steady-state model of Sr reactive transport and drainage, there is an average natural drainage flux of 0-1.4 mm/yr near the western margin of the Hanford Site, and ambient drainage may be up to 30 mm/yr in the center of the site assuming an average bulk rock weathering rate of 10-7.5 g/g/yr.
Aquifer characterization and groundwater modeling in support of remedial actions at the Weldon Spring Site
Aquifer characterization studies were performed to develop a hydrogeologic understanding of an unconfined shallow aquifer at the Weldon Spring site west of St. Louis, Missouri. The 88-ha site became contaminated because of uranium and thorium processing and disposal activities that took place from the 1940s through the 1960s. Slug and pumping tests provided valuable information on the lateral distribution of hydraulic conductivities, and packer tests and lithologic information were used to determine zones of contrasting hydrologic properties within the aquifer. A three-dimensional, finite- element groundwater flow model was developed and used to simulate the shallow groundwater flow system at the site. The results of this study show that groundwater flow through the system is predominantly controlled by a zone of fracturing and weathering in the upper portion of the limestone aquifer. The groundwater flow model, developed and calibrated from field investigations, improved the understanding of the hydrogeology and supported decisions regarding remedial actions at the site. The results of this study illustrate the value, in support of remedial actions, of combining field investigations with numerical modeling to develop an improved understanding of the hydrogeology at the site.
Durham, L.A. [Argonne National Lab., IL (United States); Carman, J.D. [Jacobs Engineering Group, Inc., St. Charles, MO (United States)
BEE 4710. Introduction to Groundwater Spring Semester 2009
BEE 4710. Introduction to Groundwater Spring Semester 2009 Credit: 3 hours Catalogue description tracers · Regional groundwater · Geology and groundwater occurrence · Groundwater models · Water Quality: Intermediate-level study of aquifer geology, groundwater flow, and related design factors. Includes de
-reactive and reactive contaminants 4. Groundwater modeling 4.1. Introduction to finite-difference models 4.2. Models of groundwater flow 4.3. Models of contaminant transport 4.4. Available models #12;Recommended textbooks FetterCE 473/573 Groundwater Fall 2009 Course information Instructor: Prof. Chris Rehmann rehmann
BEE 4710. Introduction to Groundwater Fall Semester 2006
BEE 4710. Introduction to Groundwater Fall Semester 2006 Credit: 3 hours Catalogue description: Introduction, Field trip in afternoon Principles of groundwater flow Flow to Wells Properties of aquifiers Soil occurrence Groundwater models Water Quality Groundwater quality monitoring Vadose water quality monitoring
Modeling of thermal energy storage in groundwater aquifers
MODELING OF THERMAL ENERGY STORAGE IN GROUNDWATER AQUIFERS A Thesis by DAVID BRYAN REED Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1979... ABSTRACT Modeling of Thermal Energy Storage in Groundwater Aquifers. (December 1979) David Bryan Reed, B. S. , Texas A&M University Chairman of Advisory Committee: Dr. Donald L. Reddell Solar energy is a promising alternate energy source for space heat...
Reed, David Bryan
Phase II Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 98: Frenchman Flat, Nye County, Nevada, Rev. No.: 0
This report documents pertinent transport data and data analyses as part of the Phase II Corrective Action Investigation (CAI) for Frenchman Flat (FF) Corrective Action Unit (CAU) 98. The purpose of this data compilation and related analyses is to provide the primary reference to support parameterization of the Phase II FF CAU transport model.
DeNovio, Nicole M.; Bryant, Nathan; King, Chrissi B.; Bhark, Eric; Drellack, Sigmund L.; Pickens, John F.; Farnham, Irene; Brooks, Keely M.; Reimus, Paul; Aly, Alaa
Seasonal dynamics in costal aquifers : investigation of submarine groundwater discharge through field measurements and numerical models
The fresh and saline groundwater flowing from coastal aquifers into the ocean comprise submarine groundwater discharge (SGD). This outflow is an important pathway for the transport of nutrients and contaminants, and has ...
Michael, Holly Anne, 1976-
Site-Scale Saturated Zone Flow Model
The purpose of this model report is to document the components of the site-scale saturated-zone flow model at Yucca Mountain, Nevada, in accordance with administrative procedure (AP)-SIII.lOQ, ''Models''. This report provides validation and confidence in the flow model that was developed for site recommendation (SR) and will be used to provide flow fields in support of the Total Systems Performance Assessment (TSPA) for the License Application. The output from this report provides the flow model used in the ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The Site-Scale Saturated Zone Transport model then provides output to the SZ Transport Abstraction Model (BSC 2003 [164870]). In particular, the output from the SZ site-scale flow model is used to simulate the groundwater flow pathways and radionuclide transport to the accessible environment for use in the TSPA calculations. Since the development and calibration of the saturated-zone flow model, more data have been gathered for use in model validation and confidence building, including new water-level data from Nye County wells, single- and multiple-well hydraulic testing data, and new hydrochemistry data. In addition, a new hydrogeologic framework model (HFM), which incorporates Nye County wells lithology, also provides geologic data for corroboration and confidence in the flow model. The intended use of this work is to provide a flow model that generates flow fields to simulate radionuclide transport in saturated porous rock and alluvium under natural or forced gradient flow conditions. The flow model simulations are completed using the three-dimensional (3-D), finite-element, flow, heat, and transport computer code, FEHM Version (V) 2.20 (software tracking number (STN): 10086-2.20-00; LANL 2003 [161725]). Concurrently, process-level transport model and methodology for calculating radionuclide transport in the saturated zone at Yucca Mountain using FEHM V 2.20 are being carried out in the model report, ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The velocity fields are calculated by the flow model, described herein, independent of the transport processes, and are then used as inputs to the transport model. Justification for this abstraction is presented in the model report, ''Saturated Zone Flow and Transport Model Abstraction'', MDL-NBS-HS-000021 (BSC 2003 [164870]).
G. Zyvoloski
Estimates of Tracer-Based Piston-Flow Ages of Groundwater From Selected Sites: National Water-Quality Assessment
Estimates of Tracer-Based Piston-Flow Ages of Groundwater From Selected Sites: National Water;Estimates of Tracer-Based Piston-Flow Ages of Groundwater from Selected Sites: National Water.N., Busenberg, Eurybiades, Widman, P.K., Casile, G.C., and Wayland, J.E., 2010, Estimates of tracer-based piston
Review and selection of unsaturated flow models
Since the 1960`s, ground-water flow models have been used for analysis of water resources problems. In the 1970`s, emphasis began to shift to analysis of waste management problems. This shift in emphasis was largely brought about by site selection activities for geologic repositories for disposal of high-level radioactive wastes. Model development during the 1970`s and well into the 1980`s focused primarily on saturated ground-water flow because geologic repositories in salt, basalt, granite, shale, and tuff were envisioned to be below the water table. Selection of the unsaturated zone at Yucca Mountain, Nevada, for potential disposal of waste began to shift model development toward unsaturated flow models. Under the US Department of Energy (DOE), the Civilian Radioactive Waste Management System Management and Operating Contractor (CRWMS M&O) has the responsibility to review, evaluate, and document existing computer models; to conduct performance assessments; and to develop performance assessment models, where necessary. This document describes the CRWMS M&O approach to model review and evaluation (Chapter 2), and the requirements for unsaturated flow models which are the bases for selection from among the current models (Chapter 3). Chapter 4 identifies existing models, and their characteristics. Through a detailed examination of characteristics, Chapter 5 presents the selection of models for testing. Chapter 6 discusses the testing and verification of selected models. Chapters 7 and 8 give conclusions and make recommendations, respectively. Chapter 9 records the major references for each of the models reviewed. Appendix A, a collection of technical reviews for each model, contains a more complete list of references. Finally, Appendix B characterizes the problems used for model testing.
Reeves, M.; Baker, N.A.; Duguid, J.O. [INTERA, Inc., Las Vegas, NV (United States)
Study of electrokinetic effects to quantify groundwater flow
An experimental study of electrokinetic effects (streaming potential) in earth materials was undertaken. The objective was to evaluate the measurement of electrokinetic effects as a method of monitoring and predicting the movement of groundwater, contaminant plumes, and other fluids in the subsurface. The laboratory experiments verified that the electrokinetic effects in earth materials are prominent, repeatable, and can be described well to first order by a pair of coupled differential equations.
Brown, S.R. [Sandia National Lab., Albuquerque, NM (United States); Haupt, R.W. [MIT Lincoln Lab., Lexington, MA (United States)
Groundwater flow and tritium migration in coastal plain sediments, Savannah River Site, South Carolina
Groundwater modeling was performed to assess groundwater flow and contaminant migration for a tritium plume at the Savannah River Site (SRS). The study supports the Corrective Measures Study and Interim Action Plan regulatory documents for the Old Radioactive Waste Burial Ground (ORWBG). Modeling scenarios were designed to provide data for an economic analysis of alternatives, and subsequently evaluate the effectiveness of the selected remedial technologies for tritium reduction to surface waters. Scenarios assessed include no action, vertical and surface barriers, pump-treat-reinject, and vertical recirculation wells. Hydrostratigraphic units in the area consist of fluvial, deltaic, and shallow marine sand, mud, and calcareous sediments that exhibit abrupt facies changes over short distances. The complex heterogeneity of the sediments, along with characterization data, and tritium contaminant source data required a three-dimensional model be developed in order to accurately illustrate the size, shape and orientation of the plume. Results demonstrate that the shallow confining zone in the region controls the migration path of the plume. The size and shape of the plume were modeled in three-dimensions using detailed core, geophysical and cone-penetrometer data, depth-discrete contaminant data, monitoring well data, and seepline/surface water samples. Three-dimensional tritium plume maps were created for the >20,000, >500 and >50 pCi/ml concentration levels. The three-dimensional plume maps and volumetric calculations indicate that 63 percent of the total activity and 12 percent of the volume above 50 pCi/ml resides in a layer less than 6-m thick riding on top of the shallow confining zone.
Harris, M.K. [Westinghouse Savannah River Company, Aiken, SC (United States); Flach, G.P.; Thayer, P.A. [Univ. of North Carolina (United States)
Recommendations for computer modeling codes to support the UMTRA groundwater restoration project
The Uranium Mill Tailings Remediation Action (UMTRA) Project is responsible for the assessment and remedial action at the 24 former uranium mill tailings sites located in the US. The surface restoration phase, which includes containment and stabilization of the abandoned uranium mill tailings piles, has a specific termination date and is nearing completion. Therefore, attention has now turned to the groundwater restoration phase, which began in 1991. Regulated constituents in groundwater whose concentrations or activities exceed maximum contaminant levels (MCLs) or background levels at one or more sites include, but are not limited to, uranium, selenium, arsenic, molybdenum, nitrate, gross alpha, radium-226 and radium-228. The purpose of this report is to recommend computer codes that can be used to assist the UMTRA groundwater restoration effort. The report includes a survey of applicable codes in each of the following areas: (1) groundwater flow and contaminant transport modeling codes, (2) hydrogeochemical modeling codes, (3) pump and treat optimization codes, and (4) decision support tools. Following the survey of the applicable codes, specific codes that can best meet the needs of the UMTRA groundwater restoration program in each of the four areas are recommended.
Tucker, M.D. [Sandia National Labs., Albuquerque, NM (United States); Khan, M.A. [IT Corp., Albuquerque, NM (United States)
Practical probabilistic ground-water modeling
Current emphasis by the public and scientific communities on environmental risk suggests that methods of probabilistic analysis for subsurface flow and transport will become more heavily utilized. Moreover, a probabilistic framework forces the explicit acknowledgement and treatment of uncertainty. The major obstruction to the effective use of probabilistic models is the determination of the statistical properties of unknown model parameters. In this paper the authors use the principal of minimum relative entropy (MRE) to determine the prior pdf, p(m) of a set of model parameters, (m) based on limited information. The pdf is of the form of a multivariate truncated exponential distribution. In this paper the authors use p(m) in Monte Carlo simulations to provide expected values in field variables such as drawdowns, pumping rates, and confidence limits. The examples presented illustrate some dangers associated with the practice in probabilistic modeling of assigning Gaussian pdf`s as priors. First, such an assumption for the input parameters actually injects more information into the problem than may actually exist, whether consciously or unconsciously. This fact is born out by comparison with minimum relative entropy theory. Second, the output parameters as suggested from the Monte Carlo analysis cannot be assumed to be Gaussian distributed even when the prior pdf is in Gaussian form. In a practical setting, the significance of this result and the approximation of Gaussian form would depend on the cost, risk, and consequences of the decision being made.
Woodbury, A. [Univ. of Manitoba, Winnipeg, Manitoba (Canada). Dept. of Civil and Geological Engineering; Render, F. [Ministry of Natural Resources, Winnipeg, Manitoba (Canada); Ulrych, T. [Univ. of British Columbia, Vancouver, British Columbia (Canada). Dept. of Geophysics and Astronomy
Three-Dimensional Groundwater Models of the 300 Area at the Hanford Site, Washington State
Researchers at Pacific Northwest National Laboratory developed field-scale groundwater flow and transport simulations of the 300 Area to support the 300-FF-5 Operable Unit Phase III Feasibility Study. The 300 Area is located in the southeast portion of the U.S. Department of Energy�s Hanford Site in Washington State. Historical operations involving uranium fuel fabrication and research activities at the 300 Area have contaminated engineered liquid-waste disposal facilities, the underlying vadose zone, and the uppermost aquifer with uranium. The main objectives of this research were to develop numerical groundwater flow and transport models to help refine the site conceptual model, and to assist assessment of proposed alternative remediation technologies focused on the 300 Area uranium plume.
Williams, Mark D.; Rockhold, Mark L.; Thorne, Paul D.; Chen, Yousu
Simulated effects of climate change on the Death Valley regional ground-water flow system, Nevada and California
The US Geological Survey, in cooperation with the US Department of Energy, is evaluating the geologic and hydrologic characteristics of the Death Valley regional flow system as part of the Yucca Mountain Project. As part of the hydrologic investigation, regional, three-dimensional conceptual and numerical ground-water-flow models have been developed to assess the potential effects of past and future climates on the regional flow system. A simulation that is based on climatic conditions 21,000 years ago was evaluated by comparing the simulated results to observation of paleodischarge sites. Following acceptable simulation of a past climate, a possible future ground-water-flow system, with climatic conditions that represent a doubling of atmospheric carbon dioxide, was simulated. The steady-state simulations were based on the present-day, steady-state, regional ground-water-flow model. The finite-difference model consisted of 163 rows, 153 columns, and 3 layers and was simulated using MODFLOWP. Climate changes were implemented in the regional ground-water-flow model by changing the distribution of ground-water recharge. Global-scale, average-annual, simulated precipitation for both past- and future-climate conditions developed elsewhere were resampled to the model-grid resolution. A polynomial function that represents the Maxey-Eakin method for estimating recharge from precipitation was used to develop recharge distributions for simulation.
D`Agnese, F.A.; O`Brien, G.M.; Faunt, C.C.; San Juan, C.A.
A Groundwater Dynamic Simulation Model: Application to the Upper San Pedro Basin
A Groundwater Dynamic Simulation Model: Application to the Upper San Pedro Basin Report Prepared by using tools such as tracers to determine groundwater travel times and this dynamic simulation modeling
Fay, Noah
MODELING OF FRIANT WATER MANAGEMENT AND GROUNDWATER Guilherme F. Marques, Marion W. Jenkins, Jay R. Lund
MODELING OF FRIANT WATER MANAGEMENT AND GROUNDWATER Guilherme F. Marques, Marion W. Jenkins, Jay R University of California, Davis April 2003 #12;MODELING OF FRIANT WATER MANAGEMENT AND GROUNDWATER Guilherme;TABLE OF CONTENTS i INTRODUCTION
Pasternack, Gregory B.
Estimation of Groundwater Flow Parameters Using Least Squares
conductivity. Wells are expensive to drill, and the cost of time, equipment and manpower to make accurate) is based on Darcy's emperical law for fluid flow through a porous media. This states that ~v = \\GammaK ~ rh
Assessing streamaquifer interactions through inverse modeling of flow routing q
Assessing streamaquifer interactions through inverse modeling of flow routing q Jozsef Szilagyi a and Nieber, 1977; Troch et al., 1993; Brutsaert and Lopez, 1998; Szilagyi et al., 1998; Par- lange et al., 2001; Szilagyi, 2003a). Knowledge of this inter- action between streamflow and groundwater during flood
Szilagyi, Jozsef
Groundwater Reactive Transport Models, 2012, 141-159 141 Fan Zhang, Gour-Tsyh (George) Yeh, Jack C. Parker and Xiaonan Shi (Eds)
Groundwater Reactive Transport Models, 2012, 141-159 141 Fan Zhang, Gour-Tsyh (George) Yeh, Jack C: Reactive Flow & Transport Code for Use on Laptops to Leadership-Class Supercomputers G. E. Hammond1 , P. C, a next-generation reactive flow and transport code for modeling subsurface processes, has been designed
Mills, Richard
Updated Conceptual Model for the 300 Area Uranium Groundwater Plume
The 300 Area uranium groundwater plume in the 300-FF-5 Operable Unit is residual from past discharge of nuclear fuel fabrication wastes to a number of liquid (and solid) disposal sites. The source zones in the disposal sites were remediated by excavation and backfilled to grade, but sorbed uranium remains in deeper, unexcavated vadose zone sediments. In spite of source term removal, the groundwater plume has shown remarkable persistence, with concentrations exceeding the drinking water standard over an area of approximately 1 km2. The plume resides within a coupled vadose zone, groundwater, river zone system of immense complexity and scale. Interactions between geologic structure, the hydrologic system driven by the Columbia River, groundwater-river exchange points, and the geochemistry of uranium contribute to persistence of the plume. The U.S. Department of Energy (DOE) recently completed a Remedial Investigation/Feasibility Study (RI/FS) to document characterization of the 300 Area uranium plume and plan for beginning to implement proposed remedial actions. As part of the RI/FS document, a conceptual model was developed that integrates knowledge of the hydrogeologic and geochemical properties of the 300 Area and controlling processes to yield an understanding of how the system behaves and the variables that control it. Recent results from the Hanford Integrated Field Research Challenge site and the Subsurface Biogeochemistry Scientific Focus Area Project funded by the DOE Office of Science were used to update the conceptual model and provide an assessment of key factors controlling plume persistence.
Zachara, John M.; Freshley, Mark D.; Last, George V.; Peterson, Robert E.; Bjornstad, Bruce N.
Addressing model bias and uncertainty in three dimensional groundwater transport forecasts for a physical aquifer experiment
Addressing model bias and uncertainty in three dimensional groundwater transport forecasts, and D. M. Rizzo (2008), Addressing model bias and uncertainty in three dimensional groundwater transport. Introduction [2] Eigbe et al. [1998] provide an excellent review of groundwater applications of the linear
Vermont, University of
Uranium-series constraints on radionuclide transport and groundwater flow at the Nopal I uranium deposit, Sierra Pena Blanca, Mexico
Uranium-series data for groundwater samples from the Nopal I uranium ore deposit were obtained to place constraints on radionuclide transport and hydrologic processes for a nuclear waste repository located in fractured, unsaturated volcanic tuff. Decreasing uranium concentrations for wells drilled in 2003 are consistent with a simple physical mixing model that indicates that groundwater velocities are low ({approx}10 m/y). Uranium isotopic constraints, well productivities, and radon systematics also suggest limited groundwater mixing and slow flow in the saturated zone. Uranium isotopic systematics for seepage water collected in the mine adit show a spatial dependence which is consistent with longer water-rock interaction times and higher uranium dissolution inputs at the front adit where the deposit is located. Uranium-series disequilibria measurements for mostly unsaturated zone samples indicate that {sup 230}Th/{sup 238}U activity ratios range from 0.005-0.48 and {sup 226}Ra/{sup 238}U activity ratios range from 0.006-113. {sup 239}Pu/{sup 238}U mass ratios for the saturated zone are <2 x 10{sup -14}, and Pu mobility in the saturated zone is >1000 times lower than the U mobility. Saturated zone mobility decreases in the order {sup 238}U{approx}{sup 226}Ra > {sup 230}Th{approx}{sup 239}Pu. Radium and thorium appear to have higher mobility in the unsaturated zone based on U-series data from fractures and seepage water near the deposit.
Goldstein, S.J.; Abdel-Fattah, A.I.; Murrell, M.T.; Dobson, P.F.; Norman, D.E.; Amato, R.S.; Nunn, A. J.
Modeling the atmospheric inputs of MTBE to groundwater systems
A numerical transport model was used to calculate the movement of methyl-t-butyl ether (MTBE) and several other volatile organic compounds (VOCs) from the atmosphere downward through the unsaturated zone and into shallow groundwater. Simulations were carried out for periods as long as 10 years to investigate whether a gaseous atmospheric MTBE source at typical ambient concentrations could account for the presence of MTBE in shallow groundwater at the types of low ug/L levels that have been found during the National Water Quality Assessment Program currently being conducted by the US Geological Survey. The simulations indicate that downward movement of MTBE to shallow groundwater will be very slow when there is no net downward movement of water through the vadose zone. For example, for a vadose zone composed of fine sand, and assuming tens of cm of infiltration, then only a few years will be required for water at a water table that is 5.0 m below ground surface to attain MTBE levels that correspond to saturation with respect to the atmospheric source gaseous concentration. An on/off atmospheric source, as might occur in the seasonal use of MTBE, will lead to concentrations in shallow groundwater that correspond to saturation with the time-averaging atmospheric source concentration.
Pankow, J.F.; Johnson, R.L. [Oregon Graduate Inst., Portland, OR (United States). Dept. of Environmental Science and Engineering; Thomson, N.R. [Univ. of Waterloo, Ontario (Canada). Dept. of Civil Engineering
Characterizing three-dimensional groundwater flow and transport
) linearize the gov- erning steady state flow equations to improve the description of the stochastic structure of the permeability distribution. A similar analytical approach is taken by Dagan (1985). Es- timates based on the maximum likelihood method... that regarded permeability ss a random variable were obtained in Loaiciga and Marino (1987a) and Loaiciga and Marino (1987b) who used a two-stage least-squares method, Rubln and Dagan (1987a), Rubin and Dagan (1987b), and Lu et al. (1988) who used a...
Hollenshead, Jeromy Todd
1 MODELING SHALLOW GROUNDWATER TABLE CONTRIBUTION TO SOIL WATER RETENTION IN THE UNSATURATED ZONE...................................................................................................................................13 CHAPTER 1 GENERAL INTRODUCTION.............................................................................................................................15 Shallow Groundwater Capillarity
Migliaccio, Kati White
Grand challenge problems in environmental modeling and remediation: Groundwater contaminant transport. Final project report 1998
The over-reaching goal of the Groundwater Grand Challenge component of the Partnership in Computational Science (PICS) was to develop and establish the massively parallel approach for the description of groundwater flow and transport and to address the problem of uncertainties in the data and its interpretation. This necessitated the development of innovative algorithms and the implementation of massively parallel computational tools to provide a suite of simulators for groundwater flow and transport in heterogeneous media. This report summarizes the activities and deliverables of the Groundwater Grand Challenge project funded through the High Performance Computing grand challenge program of the Department of Energy from 1995 through 1997.
Hydrogeologic evaluation and numerical simulation of the Death Valley regional ground-water flow system, Nevada and California
Yucca Mountain is being studied as a potential site for a high-level radioactive waste repository. In cooperation with the U.S. Department of Energy, the U.S. Geological Survey is evaluating the geologic and hydrologic characteristics of the ground-water system. The study area covers approximately 100,000 square kilometers between lat 35{degrees}N., long 115{degrees}W and lat 38{degrees}N., long 118{degrees}W and encompasses the Death Valley regional ground-water flow system. Hydrology in the region is a result of both the and climatic conditions and the complex described as dominated by interbasinal flow and may be conceptualized as having two main components: a series of relatively shallow and localized flow paths that are superimposed on deeper regional flow paths. A significant component of the regional ground-water flow is through a thick Paleozoic carbonate rock sequence. Throughout the regional flow system, ground-water flow is probably controlled by extensive and prevalent structural features that result from regional faulting and fracturing. Hydrogeologic investigations over a large and hydrogeologically complex area impose severe demands on data management. This study utilized geographic information systems and geoscientific information systems to develop, store, manipulate, and analyze regional hydrogeologic data sets describing various components of the ground-water flow system.
D`Agnese, F.A.; Faunt, C.C.; Turner, A.K.; Hill, M.C.
Groundwater Flow Systems at the Nevada Test Site, Nevada: A Synthesis of Potentiometric Contours, Hydrostratigraphy, and Geologic Structures
Contaminants introduced into the subsurface of the Nevada Test Site by underground nuclear testing are of concern to the U.S. Department of Energy and regulators responsible for protecting human health and safety. The potential for contaminant movement away from the underground test areas and into the accessible environment is greatest by groundwater transport. The primary hydrologic control on this transport is evaluated and examined through a series of contour maps developed to represent the hydraulic-head distribution within each of the major aquifers underlying the area. Aquifers were identified and their extents delineated by merging and analyzing multiple hydrostratigraphic framework models developed by other investigators from existing geologic information. A map of the hydraulic-head distribution in each major aquifer was developed from a detailed evaluation and assessment of available water-level measurements. Multiple spreadsheets that accompany this report provide pertinent water-level and geologic data by well or drill hole. Aquifers are mapped and discussed in general terms as being one of two types: alluvial-volcanic, or carbonate. Both aquifer types are subdivided and mapped as independent regional and local aquifers, based on the continuity of their component rock. Groundwater-flow directions, approximated from potentiometric contours that were developed from the hydraulic-head distribution, are indicated on the maps and discussed for each of the regional aquifers and for selected local aquifers. Hydraulic heads vary across the study area and are interpreted to range in altitude from greater than 5,000 feet in a regional alluvial-volcanic aquifer beneath a recharge area in the northern part of the study area to less than 2,300 feet in regional alluvial-volcanic and carbonate aquifers in the southwestern part of the study area. Flow directions throughout the study area are dominantly south-southwest with some local deviations. Vertical hydraulic gradients between aquifer types are downward throughout most of the study area; however, flow from the alluvial-volcanic aquifer into the underlying carbonate aquifer, where both aquifers are present, is believed to be minor because of an intervening confining unit. Limited exchange of water between aquifer types occurs by diffuse flow through the confining unit, by focused flow along fault planes, or by direct flow where the confining unit is locally absent. Interflow between regional aquifers is evaluated and mapped to define major flow paths. These flow paths delineate tributary flow systems, which converge to form intermediate and regional flow systems. The implications of these flow systems in controlling transport of radionuclides away from the underground test areas at the Nevada Test Site are briefly discussed. Additionally, uncertainties in the delineation of aquifers, the development of potentiometric contours, and the identification of flow systems are identified and evaluated. Eleven tributary flow systems and three larger flow systems are mapped in the Nevada Test Site area. Flow systems within the alluvial-volcanic aquifer dominate the western half of the study area, whereas flow systems within the carbonate aquifer are most prevalent in the southeastern half of the study area. Most of the flow in the regional alluvial-volcanic aquifer that moves through the underground testing area on Pahute Mesa is discharged to the land surface at springs and seeps in Oasis Valley. Flow in the regional carbonate aquifer is internally compartmentalized by major geologic structures, primarily thrust faults, which constrain flow into separate corridors. Contaminants that reach the regional carbonate aquifer from testing areas in Yucca and Frenchman Flats flow toward downgradient discharge areas through the Alkali Flat-Furnace Creek Ranch or Ash Meadows flow systems and their tributaries.
Fenelon, Joseph M.; Sweetkind, Donald S.; Laczniak, Randell J.
Theoretical analysis of the worthiness of Henry and Elder problems as benchmarks of density-dependent groundwater
: Groundwater-modeling; Density-dependent flow; Unsaturated flow; Contaminant transport 1. Introduction-dependent groundwater flow models M.J. Simpson a , T.P. Clement a,b,* a Centre for Water Research, Department the availability of benchmark problems for testing density-dependent groundwater models is limited, one should
Clement, Prabhakar
Groundwater Model Validation for the Project Shoal Area, Corrective Action Unit 447
Stoller has examined newly collected water level data in multiple wells at the Shoal site. On the basis of these data and information presented in the report, we are currently unable to confirm that the model is successfully validated. Most of our concerns regarding the model stem from two findings: (1) measured water level data do not provide clear evidence of a prevailing lateral flow direction; and (2) the groundwater flow system has been and continues to be in a transient state, which contrasts with assumed steady-state conditions in the model. The results of DRI's model validation efforts and observations made regarding water level behavior are discussed in the following sections. A summary of our conclusions and recommendations for a path forward are also provided in this letter report.
UZ Flow Models and Submodels
The purpose of this report is to document the unsaturated zone (UZ) flow models and submodels, as well as the flow fields that have been generated using the UZ flow model(s) of Yucca Mountain, Nevada. In this report, the term ''UZ model'' refers to the UZ flow model and the several submodels, which include tracer transport, temperature or ambient geothermal, pneumatic or gas flow, and geochemistry (chloride, calcite, and strontium) submodels. The term UZ flow model refers to the three-dimensional models used for calibration and simulation of UZ flow fields. This work was planned in the ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Section 1.2.7). The table of included Features, Events, and Processes (FEPs), Table 6.2-11, is different from the list of included FEPs assigned to this report in the ''Technical Work Plan for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Table 2.1.5-1), as discussed in Section 6.2.6. The UZ model has revised, updated, and enhanced the previous UZ model (BSC 2001 [DIRS 158726]) by incorporating the repository design with new grids, recalibration of property sets, and more comprehensive validation effort. The flow fields describe fracture-fracture, matrix-matrix, and fracture-matrix liquid flow rates, and their spatial distributions as well as moisture conditions in the UZ system. These three-dimensional UZ flow fields are used directly by Total System Performance Assessment (TSPA). The model and submodels evaluate important hydrogeologic processes in the UZ as well as geochemistry and geothermal conditions. These provide the necessary framework to test hypotheses of flow and transport at different scales, and predict flow and transport behavior under a variety of climatic conditions. In addition, the limitations of the UZ model are discussed in Section 8.11.
Y. Wu
Predictive Simulations to Assess Potential Effect of Mining Activities on Groundwater
Effect of Mining Activities on Groundwater April 23, 2010 Table of Contents 1.0 Introduction ............................................................................................ 6 2.2.2 Modifications to Groundwater Flow Model to Simulate Pond Seepage and Pumping.. 6 2.3 Results ............................................................................................................9 3.1 Changes to the Groundwater Flow Model
Netoff, Theoden
Transient Inverse Calibration of Site-Wide Groundwater Model to Hanford Operational Impacts from 1943 to 1996--Alternative Conceptual Model Considering Interaction with Uppermost Basalt Confined Aquifer
The baseline three-dimensional transient inverse model for the estimation of site-wide scale flow parameters, including their uncertainties, using data on the transient behavior of the unconfined aquifer system over the entire historical period of Hanford operations, has been modified to account for the effects of basalt intercommunication between the Hanford unconfined aquifer and the underlying upper basalt confined aquifer. Both the baseline and alternative conceptual models (ACM-1) considered only the groundwater flow component and corresponding observational data in the 3-Dl transient inverse calibration efforts. Subsequent efforts will examine both groundwater flow and transport. Comparisons of goodness of fit measures and parameter estimation results for the ACM-1 transient inverse calibrated model with those from previous site-wide groundwater modeling efforts illustrate that the new 3-D transient inverse model approach will strengthen the technical defensibility of the final model(s) and provide the ability to incorporate uncertainty in predictions related to both conceptual model and parameter uncertainty. These results, however, indicate that additional improvements are required to the conceptual model framework. An investigation was initiated at the end of this basalt inverse modeling effort to determine whether facies-based zonation would improve specific yield parameter estimation results (ACM-2). A description of the justification and methodology to develop this zonation is discussed.
Vermeul, Vincent R.; Cole, Charles R.; Bergeron, Marcel P.; Thorne, Paul D.; Wurstner, Signe K.
Ensemble modeling approach for rainfall/groundwater D. Laucelli, V. Babovic, M. Keijzer and O. Giustolisi
Ensemble modeling approach for rainfall/groundwater balancing D. Laucelli, V. Babovic, M. Keijzer words | ensemble modeling, genetic programming, groundwater, hydrology NOTATION y output variable x set GP model within the EM INTRODUCTION In the last few years, the global climate changes are gradually
Fernandez, Thomas
Quantifying the differential contributions of deep groundwater to streamflow in nested basins, using
-solute, deep groundwater and a low-solute, soil-water. The mixing model indicated 69% ± 10% deep groundwater-member mixing, hydrological pathway, interbasin groundwater flow INTRODUCTION Knowledge of hydrological pathwaysQuantifying the differential contributions of deep groundwater to streamflow in nested basins
Chappell, Nick A
Remote sensing for groundwater modelling in large semiarid areas: Lake Chad Basin, Africa
is lower than 200 mm and the population density does not exceed 0.05 inhabitants per km2 . PreviousRemote sensing for groundwater modelling in large semiarid areas: Lake Chad Basin, Africa Marc.springerlink.com #12;2 Remote sensing for groundwater modelling in large semiarid areas: Lake Chad Basin, Africa Marc
Transient Inverse Calibration of Hanford Site-Wide Groundwater Model to Hanford Operational Impacts - 1943 to 1996
This report describes a new initiative to strengthen the technical defensibility of predictions made with the Hanford site-wide groundwater flow and transport model. The focus is on characterizing major uncertainties in the current model. PNNL will develop and implement a calibration approach and methodology that can be used to evaluate alternative conceptual models of the Hanford aquifer system. The calibration process will involve a three-dimensional transient inverse calibration of each numerical model to historical observations of hydraulic and water quality impacts to the unconfined aquifer system from Hanford operations since the mid-1940s.
Cole, Charles R.; Bergeron, Marcel P.; Wurstner, Signe K.; Thorne, Paul D.; Orr, Samuel; Mckinley, Mathew I.
Multiscale modeling in granular flow
Granular materials are common in everyday experience, but have long-resisted a complete theoretical description. Here, we consider the regime of slow, dense granular flow, for which there is no general model, representing ...
Rycroft, Christopher Harley
of Mechanical and Aerospace Engineering Stillwater, Oklahoma KEY WORDS computer simulation, ground properties of soils and rocks were compiled from the literature. These data were used as subsequent input
Effect of hydrological flow pattern on groundwater arsenic concentration in Bangladesh by Khandaker Ashfaque.
Widespread arsenic contamination of groundwater has become a major concern in Bangladesh since the water supply, particularly in rural areas, is heavily dependent on groundwater. However, relative to the extent of research ...
Ashfaque, Khandaker
.email@example.com 2. ENVIROS, Spain S.L., Passeig de Rubí 29-31, 08197 Valldoreix Spain, firstname.lastname@example.com 3 performed by 4 teams (ANTEA, ENSMP, ENVIROS and INERIS) to simulate a contamination of groundwater is the evaluation of the fate of pollutants in groundwaters and soils. This knowledge is based on the result
Boyer, Edmond
Regional groundwater modeling of the saturated zone in the vicinity of Yucca Mountain, Nevada; Iterative Performance Assessment, Phase 2
Results of groundwater modeling of the saturated zone in the vicinity of Yucca Mountain are presented. Both a regional (200 {times} 200 km) and subregional (50 {times} 50 km) model were used in the analyses. Simulations were conducted to determine the impact of various disruptive that might take place over the life span of a proposed Yucca Mountain geologic conditions repository on the groundwater flow field, as well as changes in the water-table elevations. These conditions included increases in precipitation and groundwater recharge within the regional model, changes in permeability of existing hydrogeologic barriers, a:nd the vertical intrusion of volcanic dikes at various orientations through the saturated zone. Based on the regional analysis, the rise in the water-table under Yucca Mountain due to various postulated conditions ranged from only a few meters to 275 meters. Results of the subregional model analysis, which was used to simulate intrusive dikes approximately 4 kilometers in length in the vicinity of Yucca Mountain, showed water-table rises ranging from a few meters to as much as 103 meters. Dikes oriented approximately north-south beneath Yucca Mountain produced the highest water-table rises. The conclusions drawn from this analysis are likely to change as more site-specific data become available and as the assumptions in the model are improved.
Ahola, M.; Sagar, B. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses
Conceptual Models for Migration of Key Groundwater Contaminants Through the Vadose Zone and Into the Upper Unconfined Aquifer Below the B-Complex
The B-Complex contains 3 major crib and trench disposal sites and 3 SST farms that have released nearly 346 mega-liters of waste liquids containing the following high groundwater risk drivers: ~14,000 kg of CN, 29,000 kg of Cr, 12,000 kg of U and 145 Ci of Tc-99. After a thorough review of available vadose zone sediment and pore water, groundwater plume, field gamma logging, field electrical resistivity studies, we developed conceptual models for which facilities have been the significant sources of the contaminants in the groundwater and estimated the masses of these contaminants remaining in the vadose zone and currently present in the groundwater in comparison to the totals released. This allowed us to make mass balance calculations on how consistent our knowledge is on the current deep vadose zone and groundwater distribution of contaminants. Strengths and weaknesses of the conceptual models are discussed as well as implications on future groundwater and deep vadose zone remediation alternatives. Our hypothesized conceptual models attribute the source of all of the cyanide and most of the Tc-99 currently in the groundwater to the BY cribs. The source of the uranium is the BX-102 tank overfill event and the source of most of the chromium is the B-7-A&B and B-8 cribs. Our mass balance estimates suggest that there are much larger masses of U, CN, and Tc remaining in the deep vadose zone within ~20 ft of the water table than is currently in the groundwater plumes below the B-Complex. This hypothesis needs to be carefully considered before future remediation efforts are chosen. The masses of these groundwater risk drivers in the the groundwater plumes have been increasing over the last decade and the groundwater plumes are migrating to the northwest towards the Gable Gap. The groundwater flow rate appears to flucuate in response to seasonal changes in hydraulic gradient. The flux of contaminants out of the deep vadose zone from the three proposed sources also appears to be transient such that the evolution of the contaminant plumes is transient.
Serne, R. Jeffrey; Bjornstad, Bruce N.; Keller, Jason M.; Thorne, Paul D.; Lanigan, David C.; Christensen, J. N.; Thomas, Gregory S.
Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West Africa
1 Integrated modelling and assessment of regional groundwater resources in Germany and Benin, West.J.S. SONNEVELD [1] Institute of Hydraulic Engineering, Universitaet Stuttgart, Germany (Roland Conservation University of Bonn, Germany [3] Institute of Landscape Planning and Ecology, University
Cirpka, Olaf Arie
Modeling the Effects of Groundwater-fed Irrigation on Terrestrial Hydrology over the Conterminous United States
Human alteration of the land surface hydrologic cycle is substantial. Recent studies suggest that local water management practices including groundwater pumping and irrigation could significantly alter the quantity and distribution of water in the terrestrial system, with potential impacts on weather and climate through land-atmosphere feedbacks. In this study, we incorporated a groundwater withdrawal scheme into the Community Land Model version 4 (CLM4). To simulate the impact of irrigation realistically, we calibrated the CLM4 simulated irrigation amount against observations from agriculture census at the county scale over the conterminous United States (CONUS). The water used for irrigation was then removed from the surface runoff and groundwater aquifer according to a ratio determined from the county-level agricultural census data. Based on the simulations, the impact of groundwater withdrawals for irrigation on land surface and subsurface fluxes were investigated. Our results suggest that the impacts of irrigation on latent heat flux and potential recharge when water is withdrawn from surface water alone or from both surface and groundwater are comparable and local to the irrigation areas. However, when water is withdrawn from groundwater for irrigation, greater effects on the subsurface water balance were found, leading to significant depletion of groundwater storage in regions with low recharge rate and high groundwater exploitation rate. Our results underscore the importance of local hydrologic feedbacks in governing hydrologic response to anthropogenic change in CLM4 and the need to more realistically simulate the two-way interactions among surface water, groundwater, and atmosphere to better understand the impacts of groundwater pumping on irrigation efficiency and climate.
Leng, Guoyong; Huang, Maoyi; Tang, Qiuhong; Gao, Huilin; Leung, Lai-Yung R.
Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...
Broader source: Energy.gov (indexed) [DOE]
Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary...
1.72 Groundwater Hydrology, Fall 2004
Fundamentals of subsurface flow and transport, emphasizing the role of groundwater in the hydrologic cycle, the relation of groundwater flow to geologic structure, and the management of contaminated groundwater. Topics ...
Harvey, Charles
Stochastic models for turbulent reacting flows
The goal of this program is to develop and apply stochastic models of various processes occurring within turbulent reacting flows in order to identify the fundamental mechanisms governing these flows, to support experimental studies of these flows, and to further the development of comprehensive turbulent reacting flow models.
Kerstein, A. [Sandia National Laboratories, Livermore, CA (United States)
Inversion of Gravity Data to Define the Pre-Cenozoic Surface and Regional Structures Possibly Influencing Groundwater Flow in the Rainier Mesa Region, Nye County, Nevada.
A three-dimensional inversion of gravity data from the Rainier Mesa area and surrounding regions reveals a topographically complex pre-Cenozoic basement surface. This model of the depth to pre-Cenozoic basement rocks is intended for use in a 3D hydrogeologic model being constructed for the Rainier Mesa area. Prior to this study, our knowledge of the depth to pre-Cenozoic basement rocks was based on a regional model, applicable to general studies of the greater Nevada Test Site area but inappropriate for higher resolution modeling of ground-water flow across the Rainier Mesa area. The new model incorporates several changes that lead to significant improvements over the previous regional view. First, the addition of constraining wells, encountering old volcanic rocks lying above but near pre-Cenozoic basement, prevents modeled basement from being too shallow. Second, an extensive literature and well data search has led to an increased understanding of the change of rock density with depth in the vicinity of Rainier Mesa. The third, and most important change, relates to the application of several depth-density relationships in the study area instead of a single generalized relationship, thereby improving the overall model fit. In general, the pre-Cenozoic basement surface deepens in the western part of the study area, delineating collapses within the Silent Canyon and Timber Mountain caldera complexes, and shallows in the east in the Eleana Range and Yucca Flat regions, where basement crops out. In the Rainier Mesa study area, basement is generally shallow (< 1 km). The new model identifies previously unrecognized structures within the pre-Cenozoic basement that may influence ground-water flow, such as a shallow basement ridge related to an inferred fault extending northward from Rainier Mesa into Kawich Valley.
Thomas G. Hildenbrand; Geoffrey A. Phelps; Edward A. Mankinen
Modelling the long-term evolution of groundwater's quality in a flooded iron-ore mine using a reactive transport pipe network model
Modelling the long-term evolution of groundwater's quality in a flooded iron- ore mine using, groundwater quality, ePanet Introduction in lorraine (France), industrial mining began in the 19th century make classic groundwater modelling insuitable for predicting the impact of mining activities
Integration of Groundwater Transport Models with Wireless Sensor Networks
~nigo Urteaga2 , Qi Han2 , Anura Jayasumana3 , Tissa Illangasekare1 1 Division of Environmental Sciences dynamic hydrological and environmental processes. As the wireless nodes are resource constrained, mass be conceptualized in the WSN context. INTRODUCTION As groundwater contamination is an established problem with many
Han, Qi "Chee"
Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nye County, Nevada, Revision 0
This report documents transport data and data analyses for Yucca Flat/Climax Mine CAU 97. The purpose of the data compilation and related analyses is to provide the primary reference to support parameterization of the Yucca Flat/Climax Mine CAU transport model. Specific task objectives were as follows: � Identify and compile currently available transport parameter data and supporting information that may be relevant to the Yucca Flat/Climax Mine CAU. � Assess the level of quality of the data and associated documentation. � Analyze the data to derive expected values and estimates of the associated uncertainty and variability. The scope of this document includes the compilation and assessment of data and information relevant to transport parameters for the Yucca Flat/Climax Mine CAU subsurface within the context of unclassified source-term contamination. Data types of interest include mineralogy, aqueous chemistry, matrix and effective porosity, dispersivity, matrix diffusion, matrix and fracture sorption, and colloid-facilitated transport parameters.
Recent Approaches to Modeling Transport of Mercury in Surface Water and Groundwater - Case Study in Upper East Fork Poplar Creek, Oak Ridge, TN - 13349
In this case study, groundwater/surface water modeling was used to determine efficacy of stabilization in place with hydrologic isolation for remediation of mercury contaminated areas in the Upper East Fork Poplar Creek (UEFPC) Watershed in Oak Ridge, TN. The modeling simulates the potential for mercury in soil to contaminate groundwater above industrial use risk standards and to contribute to surface water contamination. The modeling approach is unique in that it couples watershed hydrology with the total mercury transport and provides a tool for analysis of changes in mercury load related to daily precipitation, evaporation, and runoff from storms. The model also allows for simulation of colloidal transport of total mercury in surface water. Previous models for the watershed only simulated average yearly conditions and dissolved concentrations that are not sufficient for predicting mercury flux under variable flow conditions that control colloidal transport of mercury in the watershed. The transport of mercury from groundwater to surface water from mercury sources identified from information in the Oak Ridge Environmental Information System was simulated using a watershed scale model calibrated to match observed daily creek flow, total suspended solids and mercury fluxes. Mercury sources at the former Building 81-10 area, where mercury was previously retorted, were modeled using a telescopic refined mesh with boundary conditions extracted from the watershed model. Modeling on a watershed scale indicated that only source excavation for soils/sediment in the vicinity of UEFPC had any effect on mercury flux in surface water. The simulations showed that colloidal transport contributed 85 percent of the total mercury flux leaving the UEFPC watershed under high flow conditions. Simulation of dissolved mercury transport from liquid elemental mercury and adsorbed sources in soil at former Building 81-10 indicated that dissolved concentrations are orders of magnitude below a target industrial groundwater concentration beneath the source and would not influence concentrations in surface water at Station 17. This analysis addressed only shallow concentrations in soil and the shallow groundwater flow path in soil and unconsolidated sediments to UEFPC. Other mercury sources may occur in bedrock and transport though bedrock to UEFPC may contribute to the mercury flux at Station 17. Generally mercury in the source areas adjacent to the stream and in sediment that is eroding can contribute to the flux of mercury in surface water. Because colloidally adsorbed mercury can be transported in surface water, actions that trap colloids and or hydrologically isolate surface water runoff from source areas would reduce the flux of mercury in surface water. Mercury in soil is highly adsorbed and transport in the groundwater system is very limited under porous media conditions. (authors)
Bostick, Kent; Daniel, Anamary [Professional Project Services, Inc., Bethel Valley Road, Oak Ridge, TN, 37922 (United States)] [Professional Project Services, Inc., Bethel Valley Road, Oak Ridge, TN, 37922 (United States); Tachiev, Georgio [Florida International University, Applied Research Center 10555 W. Flagler St., EC 2100 Miami Florida 33174 (United States)] [Florida International University, Applied Research Center 10555 W. Flagler St., EC 2100 Miami Florida 33174 (United States); Malek-Mohammadi, Siamak [Bradley University, 413A Jobst Hall, Preoria, IL 61625 (United States)] [Bradley University, 413A Jobst Hall, Preoria, IL 61625 (United States)
Modeling Fluid Flow in Natural Systems, Model Validation and...
rock, flow is primarily in relatively sparse networks of fractures. Discrete fracture network (DFNs) models are an approach to representing flow in fractured rock that...
Pajarito Plateau Groundwater Flow and Transport Modeling Process-Level and Systems Models of Groundwater Flow and
explosive components for the U.S. nuclear weapons program. Although the methodology is implemented for TA-16 Laboratory facility established in the 1940s to develop explosive formulations, and to assemble and test
Lu, Zhiming
WHICH HYDRAULIC MODEL TO USE IN VERTICAL FLOW CONSTRUCTED WETLANDS? Ania Morvannoua , Nicolas-equilibrium model, preferential flow path, vertical flow constructed wetlands INTRODUCTION Constructed wetlands (CWs
Games, Role-Playing, Tools and Models as a Learning Process to Simulate Groundwater Management Negotiation
Games, Role-Playing, Tools and Models as a Learning Process to Simulate Groundwater Management in answering this question at a local level. A negotiation support simulator for a regional project is proposed which includes the numerous actors involved in water resource management projects. This simulator
Paris-Sud XI, Universit� de
13 In Situ: Groundwater Bioremediation
and Bioaugmentation of Groundwater ............................ 2589 5 Intrinsic Bioremediation and Modeling attenuation. 1 Introduction A patent for in situ bioremediation of groundwater contaminated with gasoline13 In Situ: Groundwater Bioremediation T. C. Hazen Lawrence Berkeley National Laboratory, Berkeley
Hazen, Terry
Simplicity versus complexity in modelling groundwater recharge in Chalk catchments Hydrology and Earth System Sciences, 6(5), 927937 (2002) EGS
rainfall. Keywords: Chalk, modelling, groundwater recharge Introduction The Chalk is the main aquiferSimplicity versus complexity in modelling groundwater recharge in Chalk catchments 927 Hydrology and Earth System Sciences, 6(5), 927937 (2002) © EGS Simplicity versus complexity in modelling groundwater
Probability distributions of hydraulic conductivity for the hydrogeologic units of the Death Valley regional ground-water flow system, Nevada and California
The use of geologic information such as lithology and rock properties is important to constrain conceptual and numerical hydrogeologic models. This geologic information is difficult to apply explicitly to numerical modeling and analyses because it tends to be qualitative rather than quantitative. This study uses a compilation of hydraulic-conductivity measurements to derive estimates of the probability distributions for several hydrogeologic units within the Death Valley regional ground-water flow system, a geologically and hydrologicaly complex region underlain by basin-fill sediments, volcanic, intrusive, sedimentary, and metamorphic rocks. Probability distributions of hydraulic conductivity for general rock types have been studied previously; however, this study provides more detailed definition of hydrogeologic units based on lithostratigraphy, lithology, alteration, and fracturing and compares the probability distributions to the aquifer test data. Results suggest that these probability distributions can be used for studies involving, for example, numerical flow modeling, recharge, evapotranspiration, and rainfall runoff. These probability distributions can be used for such studies involving the hydrogeologic units in the region, as well as for similar rock types elsewhere. Within the study area, fracturing appears to have the greatest influence on the hydraulic conductivity of carbonate bedrock hydrogeologic units. Similar to earlier studies, we find that alteration and welding in the Tertiary volcanic rocks greatly influence conductivity. As alteration increases, hydraulic conductivity tends to decrease. Increasing degrees of welding appears to increase hydraulic conductivity because welding increases the brittleness of the volcanic rocks, thus increasing the amount of fracturing.
Belcher, W.R.; Sweetkind, D.S.; Elliott, P.E.
Groundwater monitoring program plan and conceptual site model for the Al-Tuwaitha Nuclear Research Center in Iraq.
The Radiation Protection Center of the Iraqi Ministry of Environment is developing a groundwater monitoring program (GMP) for the Al-Tuwaitha Nuclear Research Center located near Baghdad, Iraq. The Al-Tuwaitha Nuclear Research Center was established in about 1960 and is currently being cleaned-up and decommissioned by Iraq's Ministry of Science and Technology. This Groundwater Monitoring Program Plan (GMPP) and Conceptual Site Model (CSM) support the Radiation Protection Center by providing:A CSM describing the hydrogeologic regime and contaminant issues,recommendations for future groundwater characterization activities, anddescriptions of the organizational elements of a groundwater monitoring program. The Conceptual Site Model identifies a number of potential sources of groundwater contamination at Al-Tuwaitha. The model also identifies two water-bearing zones (a shallow groundwater zone and a regional aquifer). The depth to the shallow groundwater zone varies from approximately 7 to 10 meters (m) across the facility. The shallow groundwater zone is composed of a layer of silty sand and fine sand that does not extend laterally across the entire facility. An approximately 4-m thick layer of clay underlies the shallow groundwater zone. The depth to the regional aquifer varies from approximately 14 to 17 m across the facility. The regional aquifer is composed of interfingering layers of silty sand, fine-grained sand, and medium-grained sand. Based on the limited analyses described in this report, there is no severe contamination of the groundwater at Al-Tuwaitha with radioactive constituents. However, significant data gaps exist and this plan recommends the installation of additional groundwater monitoring wells and conducting additional types of radiological and chemical analyses.
Copland, John Robin; Cochran, John Russell
Quasi-three dimensional ground-water modeling of the hydrologic influence of paleozoic rocks on the ground-water table at Yucca Mountain, Nevada
north of the repository site. This study investigates the cause of the steep gradient, based on the possible influence by Paleozoic rocks under the Yucca Mountain area. A quasi-three dimensional, steady-state, finite-difference model of the groundwater...
Lee, Si-Yong
Conservation Law Models for Traffic Flow
Conservation Law Models for Traffic Flow Alberto Bressan Mathematics Department, Penn State University http://www.math.psu.edu/bressan/ Alberto Bressan (Penn State) Scalar Conservation Laws 1 / 117 #12;Review of hyperbolic conservation laws Models of traffic flow, on a single road and on a network of roads
Bressan, Alberto
Groundwater in the Great Plains
7 The importance of conservation 7 What is Groundwater? The Hydrologic Cycle 8 Groundwater flow patterns 9 Saturated and unsaturated zones 9 Aquifers 10 Sole source aquifers 10 Water wells 12 Groundwater Quality Contamination and pollution, measuring... The High Plains Aquifer 22 Population served by groundwater 23 Competing uses for a limited resource 23 Groundwater declines 24 Contamination and Health Issues Water Testing 26 Regulatory Standards, Treatment Options 27 Table of Contents 3 Public...
Jensen, R.
Water-Level Data Analysis for the Saturated Zone Site-Scale Flow and Transport Model
This report is an updated analysis of water-level data performed to provide the ''Saturated Zone Site-Scale Flow Model'' (BSC 2004 [DIRS 170037]) (referred to as the saturated zone (SZ) site-scale flow model or site-scale SZ flow model in this report) with the configuration of the potentiometric surface, target water-level data, and hydraulic gradients for calibration of groundwater flow models. This report also contains an expanded discussion of uncertainty in the potentiometric-surface map. The analysis of the potentiometric data presented in Revision 00 of this report (USGS 2001 [DIRS 154625]) provides the configuration of the potentiometric surface, target heads, and hydraulic gradients for the calibration of the SZ site-scale flow model (BSC 2004 [DIRS 170037]). Revision 01 of this report (USGS 2004 [DIRS 168473]) used updated water-level data for selected wells through the year 2000 as the basis for estimating water-level altitudes and the potentiometric surface in the SZ site-scale flow and transport model domain based on an alternative interpretation of perched water conditions. That revision developed computer files containing: Water-level data within the model area (DTN: GS010908312332.002); A table of known vertical head differences (DTN: GS010908312332.003); and A potentiometric-surface map (DTN: GS010608312332.001) using an alternative concept from that presented by USGS (2001 [DIRS 154625]) for the area north of Yucca Mountain. The updated water-level data presented in USGS (2004 [DIRS 168473]) include data obtained from the Nye County Early Warning Drilling Program (EWDP) Phases I and II and data from Borehole USW WT-24. This document is based on Revision 01 (USGS 2004 [DIRS 168473]) and expands the discussion of uncertainty in the potentiometric-surface map. This uncertainty assessment includes an analysis of the impact of more recent water-level data and the impact of adding data from the EWDP Phases III and IV wells. In addition to being utilized by the SZ site-scale flow model, the water-level data and potentiometric-surface map contained within this report will be available to other government agencies and water users for groundwater management purposes. The potentiometric surface defines an upper boundary of the site-scale flow model and provides information useful to estimation of the magnitude and direction of lateral groundwater flow within the flow system. Therefore, the analysis documented in this revision is important to SZ flow and transport calculations in support of total system performance assessment (TSPA).
K. Rehfeldt
This Analysis/Model Report (AMR) documents an updated analysis of water-level data performed to provide the saturated-zone, site-scale flow and transport model (CRWMS M&O 2000) with the configuration of the potentiometric surface, target water-level data, and hydraulic gradients for model calibration. The previous analysis was presented in ANL-NBS-HS-000034, Rev 00 ICN 01, Water-Level Data Analysis for the Saturated Zone Site-Scale Flow and Transport Model (USGS 2001). This analysis is designed to use updated water-level data as the basis for estimating water-level altitudes and the potentiometric surface in the SZ site-scale flow and transport model domain. The objectives of this revision are to develop computer files containing (1) water-level data within the model area (DTN: GS010908312332.002), (2) a table of known vertical head differences (DTN: GS0109083 12332.003), and (3) a potentiometric-surface map (DTN: GS010608312332.001) using an alternate concept from that presented in ANL-NBS-HS-000034, Rev 00 ICN 01 for the area north of Yucca Mountain. The updated water-level data include data obtained from the Nye County Early Warning Drilling Program (EWDP) and data from borehole USW WT-24. In addition to being utilized by the SZ site-scale flow and transport model, the water-level data and potentiometric-surface map contained within this report will be available to other government agencies and water users for ground-water management purposes. The potentiometric surface defines an upper boundary of the site-scale flow model, as well as provides information useful to estimation of the magnitude and direction of lateral ground-water flow within the flow system. Therefore, the analysis documented in this revision is important to SZ flow and transport calculations in support of total system performance assessment.
P. Tucci
Fluid Flow Modeling in Fractures
In this paper we study fluid flow in fractures using numerical simulation and address the challenging issue of hydraulic property characterization in fractures. The methodology is based on Computational Fluid Dynamics, ...
Sarkar, Sudipta
E-Print Network 3.0 - assessing groundwater model Sample Search...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
surveys, groundwater chemistry data, and groundwater level data were... Effects of rainwater-harvesting-induced artificial ... Source: McClain, Michael - Department of...
Energy Flow Models for the Steel Industry
each step is calibrated against Commerce Dept. data. Third, a detailed energy flow model is presented for coke ovens and blast furnaces, two very energy-intensive steps in our seven step model of steelmaking. This process-step model is calibrated...
Hyman, B.; Andersen, J. P.
Microgravity Flow Regime Transition Modeling
apparatus have been used in past flow regime mapping experiments such as Venturi, perforated pipe, annular, and t-junction mixers. The mixing apparatus used in a particular experiment determines the bubble size distribution at the inlet... pressure of 80 kPa was reported, however, the temperature was not. The orientation and location of the test section with respect to the aircraft are unknown. The mixing apparatus used in the experiment was a Venturi mixer. This data set does...
Shephard, Adam M.
Lakes & Reservoirs: Research and Management 2002 7: 189199 Modelling the impact of historical land uses on
uses on surface-water quality using groundwater flow and solute-transport models Karen G. Wayland,1-use effects on surface-water quality. Key words groundwater lag time, groundwater modelling, land use, water quality, watersheds. INTRODUCTION The biogeochemistry of surface water and groundwater are related to land
, 60550 Verneuil-en-Halatte - France, email@example.com 2. ENVIROS, Spain S.L., Passeig de Rubi 29-31, 08197 Valldoreix - Spain, email@example.com 3. ANTEA, Direction Technique, 3 avenue Claude Guillemin in order to bring a better and common practice of the use of transport models concerning various pollutants
Groundwater Recharge Simulator M. Tech. Thesis
;Contents 1 Introduction 1 1.1 Groundwater Theory . . . . . . . . . . . . . . . . . . . . . . . . . . 23 1.4 Groundwater Modelling System(GMS) . . . . . . . . . . . . . . . . . . . . 24 1.5 Chapter Reservoir/Lake Modelling 44 3.1 Lake and Groundwater Interaction
Regional groundwater flow paths in Trans-Pecos, Texas inferred from oxygen,
isotopes Matthew M. Uliana a,*, Jay L. Banner b , John M. Sharp Jr. b a Department of Earth and hydrogen, oxygen, and strontium isotopes. dD and d18 O values fall close to the global meteoric water line in the alluvial fill at the upgradient end of the flow system. ª 2006 Elsevier B.V. All rights reserved. 0022
Banner, Jay L.
Assessment of managed aquifer recharge site suitability and influence using a GIS and3 numerical modeling4
" for20 MAR. Results from the GIS analysis were used with a regional groundwater model to assess the groundwater flowing to the ocean over the long term. Modeling results28 illustrate considerable variability evaluation of options for32 enhancing groundwater resources.33 34 1. Introduction35 Groundwater
Fisher, Andrew
A model for transonic plasma flow
A linear, two-dimensional model of a transonic plasma flow in equilibrium is constructed and given an explicit solution in the form of a complex Laplace integral. The solution indicates that the transonic state can be solved as an elliptic boundary value problem, as is done in the numerical code FLOW [Guazzotto et al., Phys. Plasmas 11, 604 (2004)]. Moreover, the presence of a hyperbolic region does not necessarily imply the presence of a discontinuity or any other singularity of the solution.
Guazzotto, Luca, E-mail: firstname.lastname@example.com [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)] [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Hameiri, Eliezer, E-mail: email@example.com [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)] [Courant Institute of Mathematical Sciences, New York University, New York, New York 10012 (United States)
An integral-balance nonlinear model to simulate changes in soil moisture, groundwater and surface runoff dynamics at the hillslope scale
An integral-balance nonlinear model to simulate changes in soil moisture, groundwater and surface-state integral-balance model for soil moisture and groundwater dynamics. Development of the model was motivated. �? 2014 Elsevier Ltd. All rights reserved. 1. Introduction Recent studies on the modeling
Jay, Laurent O.
Multigrid and Krylov Solvers for Large Scale Finite Element Groundwater Flow Simulations on Distributed Memory Parallel Platforms
In this report we present parallel solvers for large linear systems arising from the finite-element discretization of the three-dimensional steady-state groundwater flow problem. Our solvers are based on multigrid and Krylov subspace methods. The parallel implementation is based on a domain decomposition strategy with explicit message passing using NX and MPI libraries. We have tested our parallel implementations on the Intel Paragon XP/S 150 supercomputer using up to 1024 parallel processors and on other parallel platforms such as SGI/Power Challenge Array, Cray/SGI Origin 2000, Convex Exemplar SPP-1200, and IBM SP using up to 64 processors. We show that multigrid can be a scalable algorithm on distributed memory machines. We demonstrate the effectiveness of parallel multigrid based solvers by solving problems requiring more than 70 million nodes in less than a minute. This is more than 25 times faster than the diagonal preconditioned conjugate gradient method which is one of the more popular methods for large sparse linear systems. Our results also show that multigrid as a stand alone solver works best for problems with smooth coefficients, but for rough coefficients it is best used as a preconditioner for a Krylov subspace method such as the conjugate gradient method. We show that even for extremely heterogeneous systems the multigrid pre-conditioned conjugate gradient method is at least 10 times faster than the diagonally preconditioned conjugate gradient method.
Mahinthakumar, K.
Uranium Removal from Groundwater via In Situ Biostimulation: Field-Scale Modeling of Transport and Biological Processes
During 2002 and 2003, bioremediation experiments in the unconfined aquifer of the Old Rifle UMTRA field site in western Colorado provided evidence for the immobilization of hexavalent uranium in groundwater by iron-reducing Geobacter sp. stimulated by acetate amendment. As the bioavailable Fe(III) terminal electron acceptor was depleted in the zone just downgradient of the acetate injection gallery, sulfate-reducing organisms came to dominate the microbial community. In the present study, we use multicomponent reactive transport modeling to analyze data from the 2002 field experiment to 1) identify the dominant transport and biological processes controlling uranium mobility during biostimulation, 2) determine field-scale parameters for these modeled processes, and 3) apply the calibrated process models to history match observations during the 2003 field experiment. In spite of temporally and spatially variable observations during the field-scale biostimulation experiments, the coupled process simulation approach was able to establish a quantitative characterization of the principal flow, transport, and reaction processes that could be applied without modification to describe the 2003 field experiment. Insights gained from this analysis include field-scale estimates of bioavailable Fe(III) mineral, and the magnitude of uranium bioreduction during biostimulated growth of the iron-reducing and sulfate-reducing microorganisms.
Yabusaki, Steven B.; Fang, Yilin; Long, Philip E.; Resch, Charles T.; Peacock, Aaron D.; Komlos, John; Jaffe, Peter R.; Morrison, Stan J.; Dayvault, Richard; White, David C.; Anderson, Robert T.
A void distribution model-flashing flow
A new model for flashing flow based on wall nucleations is proposed here and the model predictions are compared with some experimental data. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites was used. Thus it was possible to avoid the usual assumption of a constant bubble number density. Comparisons of the model with the data shows that the model based on the nucleation site density correlation appears to be acceptable to describe the vapor generation in the flashing flow. For the limited data examined, the comparisons show rather satisfactory agreement without using a floating parameter to adjust the model. This result indicated that, at least for the experimental conditions considered here, the mechanistic predictions of the flashing phenomenon is possible on the present wall nucleation based model.
Riznic, J.; Ishii, M.; Afgan, N.
2000 Annual Interim Sanitary Landfill Groundwater Monitoring Report
This report includes a discussion of the groundwater flow direction and rate, the groundwater analytical results, and the methane monitoring results.
Chase, J.A.
Efficient Production Optimization Using Flow Network Models
of the physical processes that govern the long-term behavior of the reservoir. We present an alternative solution that combines the advantages of both statistics-based and physics-based methods by deriving the flow predictions in complex two-dimensional models...
Lerlertpakdee, Pongsathorn
approaches pursued were based on using : (i) linear or nonlinear Shallow Water Wave equations (Carrier approaches. Griffiths et al. 28 1992, compared measurements of internal kinematics of periodic waves shoalingCHAPTER NO. FULLY NONLINEAR POTENTIAL FLOW MODELS USED FOR LONG WAVE RUNUP PREDICTION (S. Grilli
Grilli, Stéphan T.
Modeling the natural attenuation of benzene in groundwater impacted by ethanol-blended fuels: Effect of ethanol content
Modeling the natural attenuation of benzene in groundwater impacted by ethanol-blended fuels: Effect of ethanol content on the lifespan and maximum length of benzene plumes Diego E. Gomez1 and Pedro 10 March 2009. [1] A numerical model was used to evaluate how the concentration of ethanol
Alvarez, Pedro J.
"Modeling and Computation in Environmental Sciences" (R. Helmig et al, eds.), pp. 86--90. Vieweg 1997
SSOR preconditioners are an appropriate tool. INTRODUCTION In groundwater flow simulations great systems of linear models for groundwater flow problems are performed, one has typi cally domains whose projection onto groundwater is transported, has a thickness of about 10 to 100 m. To achieve a good model of the geological
Braess, Dietrich
A bulk-flow model of angled injection Lomakin bearings
A bulk-flow model for determination of the leakage and dynamic force characteristics of angled injection Lomakin bearings is presented. Zeroth- and first-order equations describe the equilibrium flow for a centered bearing and the perturbed flow...
Soulas, Thomas Antoine Theo
Causality Analysis of Groundwater dynamics based on a Vector Autoregressive model in the semi-arid basin of Gundal (South India)
Causality Analysis of Groundwater dynamics based on a Vector Autoregressive model in the semi, time space analysis, causality, VAR model, semi-arid region 1. Introduction Large amounts of water. Abstract: Causal relationships existing between observed levels of groundwater in a semi-arid sub
Data Package for Past and Current Groundwater Flow and Contamination beneath Single-Shell Tank Waste Management Areas
This appendix summarizes historic and recent groundwater data collected from the uppermost aquifer beneath the 200 East and 200 West Areas. Although the area of interest is the Hanford Site Central Plateau, most of the information discussed in this appendix is at the scale of individual single-shell tank waste management areas. This is because the geologic, and thus the hydraulic, properties and the geochemical properties (i.e., groundwater composition) are different in different parts of the Central Plateau.
Horton, Duane G.
A survey of air flow models for multizone structures
Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 50 multizone air flow models, all developed since 1966, two of which are still under development. All these programs use similar flow equations for crack flow but differ in the versatility to describe the full range of flow phenomena and the algorithm provided for solving the set of nonlinear equations. This literature review was found that newer models are able to describe and simulate the ventilation systems and interrelation of mechanical and natural ventilation. 27 refs., 2 figs., 1 tab.
Feustel, H.E.; Dieris, J.
Climate-Soil-Vegetation Control on Groundwater Table Dynamics and its Feedbacks in a Climate Model
Among the three dynamically linked branches of the water cycle, including atmospheric, surface, and subsurface water, groundwater is the largest reservoir and an active component of the hydrologic system. Because of the inherent slow response time, groundwater may be particularly relevant for long time-scale processes such as multi-years or decadal droughts. This study uses regional climate simulations with and without surface water � groundwater interactions for the conterminous U.S. to assess the influence of climate, soil, and vegetation on groundwater table dynamics, and its potential feedbacks to regional climate. Analysis shows that precipitation has a dominant influence on the spatial and temporal variations of groundwater table depth (GWT). The simulated GWT is found to decrease sharply with increasing precipitation. Our simulation also shows some distinct spatial variations that are related to soil porosity and hydraulic conductivity. Vegetation properties such as minimum stomatal resistance, and root depth and fraction are also found to play an important role in controlling the groundwater table. Comparing two simulations with and without groundwater table dynamics, we find that groundwater table dynamics mainly influences the partitioning of soil water between the surface (0 � 0.5 m) and subsurface (0.5 � 5 m) rather than total soil moisture. In most areas, groundwater table dynamics increases surface soil moisture at the expense of the subsurface, except in regions with very shallow groundwater table. The change in soil water partitioning between the surface and subsurface is found to strongly correlate with the partitioning of surface sensible and latent heat fluxes. The evaporative fraction (EF) is generally higher during summer when groundwater table dynamics is included. This is accompanied by increased cloudiness, reduced diurnal temperature range, cooler surface temperature, and increased cloud top height. Although both convective and non-convective precipitation are enhanced, the higher EF changes the partitioning to favor more non-convective precipitation, but this result could be sensitive to the convective parameterization used. Compared to simulations without groundwater table dynamics, the dry bias in the summer precipitation is slightly reduced over the central and eastern U.S. Groundwater table dynamics can provide important feedbacks to atmospheric processes, and these feedbacks are stronger in regions with deeper groundwater table, because the interactions between surface and subsurface are weak when the groundwater table is deep. This increases the sensitivity of surface soil moisture to precipitation anomalies, and therefore enhances land surface feedbacks to the atmosphere through changes in soil moisture and evaporative fraction. By altering the groundwater table depth, land use change and groundwater withdrawal can alter land surface response and feedback to the climate system.
Leung, Lai-Yung R.; Huang, Maoyi; Qian, Yun; Liang, Xu
Groundwater recharge estimates using a soil-water-balance model for the Powder River and Williston structural basins
Groundwater recharge estimates using a soil-water-balance model for the Powder River and Williston for the lower Tertiary and Upper Cretaceous aquifer system in the Powder River and Williston structural basins in the Williston structural basin will require trillions of gallons of water from this aquifer system over the next
Turbulent Flow and Transport Modeling by Long Waves and Currents
This dissertation presents models for turbulent flow and transport by currents and long waves in large domain. From the Navier-Stokes equations, a fully nonlinear depth-integrated equation model for weakly dispersive, turbulent and rotational flow...
Kim, Dae Hong
Micro level study on groundwater contaminant transport modeling of industrial pollution and hydro remediation;.
??Water pollution is a serious problem world over, as a growing percentage of surface water resources and groundwater reserves are being contaminated due to uncontrolled� (more)
Hemamalini C G
Traffic flow models and service rules for complex production systems
Traffic flow models and service rules for complex production systems C. Ringhofer Abstract We emphasis is given to the implementation of service rules for complex systems, involving multiple product flow type models for complex production systems. Traffic flow models represent, in some sense
Ringhofer, Christian
Hanford Site ground-water monitoring for 1994
This report presents the results of the Ground-Water Surveillance Project monitoring for calendar year 1994 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiologic and chemical waste that have impacted ground-water quality on the Site. Monitoring of water levels and ground-water chemistry is performed to track the extent of contamination and trends in contaminant concentrations. The 1994 monitoring was also designed to identify emerging ground-water quality problems. The information obtained is used to verify compliance with applicable environmental regulations and to evaluate remedial actions. Data from other monitoring and characterization programs were incorporated to provide an integrated assessment of Site ground-water quality. Additional characterization of the Site`s geologic setting and hydrology was performed to support the interpretation of contaminant distributions. Numerical modeling of sitewide ground-water flow also supported the overall project goals. Water-level monitoring was performed to evaluate ground-water flow directions, to track changes in water levels, and to relate such changes to changes in site disposal practices. Water levels over most of the Hanford Site continued to decline between June 1993 and June 1994. These declines are part of the continued response to the cessation of discharge to U Pond and other disposal facilities. The low permeability in this area which enhanced mounding of waste-water discharge has also slowed the response to the reduction of disposal.
Dresel, P.E.; Thorne, P.D.; Luttrell, S.P. [and others
Buying, Selling and Exporting Groundwater: Implications for Groundwater Conservation Districts
in a Sales/ Lease Agreement, by Sandra Burns. Regulation of Exportation of Underground Water, by Doug Caroom. Roberts County Transportation Permits, by C.E. Williams. Export Fees: A Groundwater District Limits and Uses, by Jace Houston. The report also... in Texas, by Ronald Kaiser. Groundwater Transactions: Buyers Perspective, by Russell Johnson. Purchasing Groundwater for Export: The Kinney County Proposal, by Lynn Sherman. Model Lease of Groundwater Rights, by Ned Meister. Protecting Your Land and Water...
Kaiser, Ronald; Lesikar, Bruce A.; Silvey, Valeen
Baroclinic flow and the Lorenz-84 model
The bifurcation diagram of a truncation to six degrees of freedom of the equations for quasi-geostrophic, baroclinic flow is investigated. Period doubling cascades and Shil'nikov bifurcations lead to chaos in this model. The low dimension of the chaotic attractor suggests the possibility to reduce the model to three degrees of freedom. In a physically comprehensible limit of the parameters this reduction is done explicitly. The bifurcation diagram of the reduced model in this limit is compared to the diagram of the six degrees of freedom model and agrees well. A numerical implementation of the graph transform is used to approximate the three dimensional invariant manifold away from the limit case. If the six dimensional model is reduced to a linearisation of the invariant manifold about the Hadley state, the Lorenz-84 model is found. Its parameters can then be calculated from the physical parameters of the quasi-geostrophic model. Bifurcation diagrams at physical and traditional parameter values are compared and routes to chaos in the Lorenz-84 model are described.
Lennaert van Veen
Observing and modeling Earths energy flows
This article reviews, from the authors perspective, progress in observing and modeling energy flows in Earth's climate system. Emphasis is placed on the state of understanding of Earth's energy flows and their susceptibility to perturbations, with particular emphasis on the roles of clouds and aerosols. More accurate measurements of the total solar irradiance and the rate of change of ocean enthalpy help constrain individual components of the energy budget at the top of the atmosphere to within {+-}2 W m{sup -2}. The measurements demonstrate that Earth reflects substantially less solar radiation and emits more terrestrial radiation than was believed even a decade ago. Active remote sensing is helping to constrain the surface energy budget, but new estimates of downwelling surface irradiance that benefit from such methods are proving difficult to reconcile with existing precipitation climatologies. Overall, the energy budget at the surface is much more uncertain than at the top of the atmosphere. A decade of high-precision measurements of the energy budget at the top of the atmosphere is providing new opportunities to track Earth's energy flows on timescales ranging from days to years, and at very high spatial resolution. The measurements show that the principal limitation in the estimate of secular trends now lies in the natural variability of the Earth system itself. The forcing-feedback-response framework, which has developed to understand how changes in Earth's energy flows affect surface temperature, is reviewed in light of recent work that shows fast responses (adjustments) of the system are central to the definition of the effective forcing that results from a change in atmospheric composition. In many cases, the adjustment, rather than the characterization of the compositional perturbation (associated, for instance, with changing greenhouse gas concentrations, or aerosol burdens), limits accurate determination of the radiative forcing. Changes in clouds contribute importantly to this adjustment and thus contribute both to uncertainty in estimates of radiative forcing and to uncertainty in the response. Models are indispensable to calculation of the adjustment of the system to a compositional change but are known to be flawed in their representation of clouds. Advances in tracking Earth's energy flows and compositional changes on daily through decadal timescales are shown to provide both a critical and constructive framework for advancing model development and evaluation.
Stevens B.; Schwartz S.
Integration of SWAP and MODFLOW-2000 for modeling groundwater dynamics in shallow water table areas
for sustainable water resources management in shallow water table areas. The hydrologic processes are highly in MODFLOW are derived from a combination of topology, soil type, land use, water management practices using and evapotranspiration is signifi- cant for sustainable groundwater management. However, the groundwater recharge
a combination of topology, soil type, land use, water management practices using geographic information systems for sustainable groundwater management. However, the groundwater recharge and evapotranspiration are influenced by a range of factors such as topography, soil type, land use, and water management practices (Petheram et al
Systematic Method for Evaluating Extraction and Injection Flow Rates for 100-KR-4 and 100-HR-3 Groundwater Operable Unit Pump-and-Treat Interim Actions for Hydraulic Containment
This document describes a systematic method to develop flow rate recommendations for Pump-and-Treat (P&T) extraction and injection wells in 100-KR-4 and 100-HR-3 Groundwater Operable Units (OU) of the Hanford Site. Flow rate recommendations are developed as part of ongoing performance monitoring and remedy optimization of the P&T interim actions to develop hydraulic contairnnent of the dissolved chromium plume in groundwater and protect the Columbia River from further discharges of groundwater from inland. This document details the methodology and data required to infer the influence of individual wells near the shoreline on hydraulic containment and river protection and develop flow rate recommendations to improve system performance and mitigate potential shortcomings of the system configuration in place.
Spiliotopoulos, Alexandros A.
Flow characteristics in an irregular spillway model
River Authority. TABLE OF CONTENTS Page ACKNOWLEDGEMENT TABLE OF CONTENTS V1 LIST OF FIGURES LIST OF TABLES INTRODUCTION REVIEW OF LITERATURE Open Channel Flow Spillways Physical Modeling METHODS AND PROCEDURES 5 5 10 16 20 RESULTS... Test Test Test Test Test Test Test Test Test Test Test Test Test Test Test Test 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ? PMF Test 27 27 29 29 32 35 38 43 43 49 49 52 56 63 63 65 65 DISCUSSION S...
Scott, Mary Charlene
Development and Testing of a Groundwater Management Model for the Faultless Underground Nuclear Test, Central Nevada Test Area
This document describes the development and application of a user-friendly and efficient groundwater management model of the Central Nevada Test Area (CNTA) and surrounding areas that will allow the U.S. Department of Energy and state personnel to evaluate the impact of future proposed scenarios. The management model consists of a simple hydrologic model within an interactive groundwater management framework. This framework is based on an object user interface that was developed by the U.S. Geological Survey and has been used by the Desert Research Institute researchers and others to couple disparate environmental resource models, manage the necessary temporal and spatial data, and evaluate model results for management decision making. This framework was modified and applied to the CNTA and surrounding Hot Creek Valley. The utility of the management model was demonstrated through the application of hypothetical future scenarios including mineral mining, regional expansion of agriculture, geothermal energy production, and export of water to large urban areas outside the region. While the results from some of the scenarios indicated potential impacts to the region near CNTA and others did not, together they demonstrate the usefulness of the management tool for managers who need to evaluate the impact proposed changes in groundwater use in or near CNTA may have on radionuclide migration.
Douglas P. Boyle; Gregg Lamorey; Scott Bassett; Greg Pohll; Jenny Chapman
Potential Flow Modelling for Wind Turbines Shane Cline
Potential Flow Modelling for Wind Turbines by Shane Cline B.Sc., University of Toledo, 2003 M means, without the permission of the author. #12;ii Potential Flow Modelling for Wind Turbines by Shane potential flow methods are a promising alternative to mainstream wind turbine aerodynamics tools
Victoria, University of
-WATER FLOW IN STRONGLY HETEROGENEOUS FORMATIONS By Hongbin Zhan1 and Stephen W. Wheatcraft2 ABSTRACT
Groundwater Fate and Transport Modeling for Texarkana Wood Preserving Company Superfund Site, Texarkana, Texas
Fate and transport model results are presented for the Texarkana Wood Preserving Company (TWPC)superfund site. The conceptual model assumes two sources of contamination, specifically, the areas around the old and new process areas. Recent data show the presence of non-aqueous phase liquids (NAPL) in the aquifer that are also sources of dissolved contamination in the aquifer. A flow model was constructed and calibrated against measured hydraulic heads at permanent monitoring wells. Good matches were obtained between model simulated heads and most measured heads. An unexplained exception occurs at monitoring well MW-13 down gradient of the site beyond the measured contaminant plume where the model predicts heads that are more than 2 ft. lower than reported field measurements. Adjusting hydraulic parameters in the model could not account for this anomaly and still preserve the head matches at other wells. There is likely a moderate deficiency in the conceptual model or perhaps a data error. Other information such as substantial amounts of infiltrating surface water in the area or a correction in surveyed elevation would improve the flow model. A particle tracking model calculated a travel time from the new process area to the Day�s Creek discharge location on the order of 40 years. Travel times from the old process area to Day�s Creek were calculated to be on the order of 80 years. While these calculations are subject to some uncertainty, travel times of decades are indicated.
Arnett, Ronald Chester
Stochastic and deterministic models for dense granular flow
Granular materials such as sand or gravel surround us everyday and yet remain poorly understood. In this thesis, two models are developed for dense granular flow, each capable of predicting flows with accuracy in multiple ...
Kamrin, Kenneth Norman
Robust performance evaluation represents one of the most challenging aspects of groundwater pump-and-treat (P&T) remedy implementation. In most cases, the primary goal of the P&T system is hydraulic containment, and ultimately recovery, of contaminants to protect downgradient receptors. Estimating the extent of hydraulic containment is particularly challenging under changing flow patterns due to variable pumping, boundaries and/or other conditions. We present a systematic approach to estimate hydraulic containment using multiple lines of evidence based on (a) water-level mapping and (b) groundwater modeling. Capture Frequency Maps (CFMs) are developed by particle tracking on water-level maps developed for each available water level data set using universal kriging. In a similar manner, Capture Efficiency Maps (CEMs) are developed by particle tracking on water-levels calculated using a transient groundwater flow model: tracking is undertaken independently for each stress period using a very low effective porosity, depicting the 'instantaneous' fate of each particle each stress period. Although conceptually similar, the two methods differ in their underlying assumptions and their limitations: their use together identifies areas where containment may be reliable (i.e., where the methods are in agreement) and where containment is uncertain (typically, where the methods disagree). A field-scale example is presented to illustrate these concepts.
Groundwater is not a Common-Pool resource: Ordering sustainability issues of groundwater use
-economic modeling Introduction Groundwater interaction with surface water bodies and dependent ecosystems of conclusions and recommendations of some economic models or social sciences approaches regarding groundwaterGroundwater is not a Common-Pool resource: Ordering sustainability issues of groundwater use
Evaluation of Collector Well Configurations to Model Hydrodynamics in Riverbank Filtration and Groundwater Remediation
Collector well designs are necessary to maximize groundwater uptake and riverbank filtration without negatively impacting an aquifer. Unfortunately, there is a lack of information and research regarding the implementation of collector well design...
De Leon, Tiffany Lucinda
Unbounded dynamics in dissipative flows: R�ssler model
Transient chaos and unbounded dynamics are two outstanding phenomena that dominate in chaotic systems with large regions of positive and negative divergences. Here, we investigate the mechanism that leads the unbounded dynamics to be the dominant behavior in a dissipative flow. We describe in detail the particular case of boundary crisis related to the generation of unbounded dynamics. The mechanism of the creation of this crisis in flows is related to the existence of an unstable focus-node (or a saddle-focus) equilibrium point and the crossing of a chaotic invariant set of the system with the weak-(un)stable manifold of the equilibrium point. This behavior is illustrated in the well-known R�ssler model. The numerical analysis of the system combines different techniques as chaos indicators, the numerical computation of the bounded regions, and bifurcation analysis. For large values of the parameters, the system is studied by means of Fenichel's theory, providing formulas for computing the slow manifold which influences the evolution of the first stages of the orbit.
Barrio, Roberto, E-mail: firstname.lastname@example.com; Serrano, Sergio, E-mail: firstname.lastname@example.com [Computational Dynamics Group, Dpto. Matem�tica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)] [Computational Dynamics Group, Dpto. Matem�tica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Blesa, Fernando, E-mail: firstname.lastname@example.com [Computational Dynamics Group, Dpto. F�sica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)] [Computational Dynamics Group, Dpto. F�sica Aplicada and IUMA, Universidad de Zaragoza, E-50009 Zaragoza (Spain)
Binary fish passage models for uniform and nonuniform flows
Binary fish passage models are considered by many fisheries managers to be the best 21 available practice for culvert inventory assessments and for fishway and barrier design. 22 Misunderstandings between different binary passage modeling approaches often arise, 23 however, due to differences in terminology, application and presentation. In this paper 24 one-dimensional binary fish passage models are reviewed and refined to clarify their 25 origins and applications. For uniform flow, a simple exhaustion-threshold (ET) model 26 equation is derived that predicts the flow speed threshold in a fishway or velocity barrier 27 that causes exhaustion at a given maximum distance of ascent. Flow speeds at or above 28 the threshold predict failure to pass (exclusion). Flow speeds below the threshold predict 29 passage. The binary ET model is therefore intuitive and easily applied to predict passage 30 or exclusion. It is also shown to be consistent with the distance-maximizing model. The 31 ET model s limitation to uniform flow is addressed by deriving a passage model that 32 accounts for nonuniform flow conditions more commonly found in the field, including 33 backwater profiles and drawdown curves. Comparison of these models with 34 experimental observations of volitional passage for Gambusia affinis in uniform and 35 nonuniform flows indicates reasonable prediction of binary outcomes (passage or 36 exclusion) if the flow speed is not near the threshold flow velocity. More research is 37 needed on fish behavior, passage strategies under nonuniform flow regimes and 38 stochastic methods that account for individual differences in swimming performance at or 39 near the threshold flow speed. Future experiments should track and measure ground 40 speeds of ascending fish to test nonuniform flow passage strategies and to improve model 41 predictions. Stochastic models, such as Monte-Carlo techniques, that account for 42 different passage performance among individuals and allow prediction of the percentage 43 of fish passing would be particularly useful near flow speed thresholds where binary 44 passage models are clearly limited.
Neary, Vincent S [ORNL
Effects of pore-scale velocity and pore-scale physical processes on contaminant biodegradation during transport in groundwater: modeling and experiments
EFFECTS OF PORE-SCALE VELOCITY AND PORE-SCALE PHYSICAL PROCESSES ON CONTAMINANT BIODEGRADATION DURING TRANSPORT IN GROUNDWATER: MODELING AND EXPERIMENTS A Dissertation by ITZA MENDOZA SANCHEZ Submitted to the Office... PROCESSES ON CONTAMINANT BIODEGRADATION DURING TRANSPORT IN GROUNDWATER: MODELING AND EXPERIMENTS A Dissertation by ITZA MENDOZA SANCHEZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...
Mendoza Sanchez, Itza
Water Modeling of Steel Flow, Air Entrainment and Filtration
Water Modeling of Steel Flow, Air Entrainment and Filtration Christoph Beckermann Associate Beckermann, C., "Water Modeling of Steel Flow, Air Entrainment and Filtration," in Proceedings of the 46th, 1992. #12;Abstract This paper presents an analysis of water modeling of steel pouring to study (1) air
Beckermann, Christoph
Hanford Site groundwater monitoring for fiscal year 1996
This report presents the results of groundwater and vadose-zone monitoring for fiscal year (FY) 1996 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiological and chemical waste that affected groundwater quality on the site. Characterization and monitoring of the vadose zone during FY 1996 comprised primarily spectral gamma logging, soil-gas monitoring, and electrical resistivity tomography. Water-level monitoring was performed to evaluate groundwater-flow directions, to track changes in water levels, and to relate such changes to evolving disposal practices. Water levels over most of the Hanford Site continued to decline between June 1995 and June 1996. Groundwater chemistry was monitored to track the extent of contamination, to note trends, and to identify emerging groundwater-quality problems. The most widespread radiological contaminant plumes were tritium and iodine-129. Smaller plumes of strontium-90, technetium-99, and plutonium also were present at levels above the U.S. Environmental Protection Agency or State of Washington interim drinking water standards. Uranium concentrations greater than the proposed drinking water standard were also observed. Nitrate, fluoride, chromium, carbon tetrachloride, chloroform, trichloroethylene, and cis-1,2-dichlomethylene were present in groundwater samples at levels above their U.S. Environmental Protection Agency or State of Washington maximum contaminant levels. The nitrate plume is the most extensive. Three-dimensional, numerical, groundwater models were applied to the Hanford Site to predict contaminant-flow paths and the impact of operational changes on site groundwater conditions. Other models were applied to assess the performance of three separate pump-and-treat systems.
Hartman, M.J.; Dresel, P.E.; Borghese, J.V. [eds.] [and others] [eds.; and others
MODELING COUPLED FLUID FLOW AND GEOMECHANICAL AND GEOPHYSICAL PHENOMENA WITHIN A FINITE ELEMENT between pore fluid flow and the concurring deformation of the solid rock matrix. The governing equations and constitutive relations of fluid flow are coupled to stress-strain relations. With the appropriate boundary
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir...
More Documents & Publications Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs Detection and Characterization of Natural...
Numerical Computation of Multiphase Flows in Porous Media
Preface iii Notation ix Introduction 1 1 Modeling Immiscible Fluid Flow in Porous Media 7 1.1 Porous Media legendi im Fachgebiet Informatik (Wissenschaftliches Rechnen) #12;ii #12;Preface Groundwater is a precious resource that is important for all forms of life on earth. The quality of groundwater is impaired
Bastian, Peter
Flow in geothermal wells: Part III. Calculation model for self-flowing well
The theoretical model described predicts the temperature, pressure, dynamic dryness fraction, and void fraction along the vertical channel of two-phase flow. The existing data from operating wells indicate good agreement with the model. (MHR)
Bilicki, Z.; Kestin, J.; Michaelides, E.E.
Processes, mechanisms, parameters, and modeling approaches for partially saturated flow in soil and rock media; Yucca Mountain Site Characterization Project
This report discusses conceptual models and mathematical equations, analyzes distributions and correlations among hydrological parameters of soils and tuff, introduces new path integration approaches, and outlines scaling procedures to model potential-driven fluid flow in heterogeneous media. To properly model the transition from fracture-dominated flow under saturated conditions to matrix-dominated flow under partially saturated conditions, characteristic curves and permeability functions for fractures and matrix need to be improved and validated. Couplings from two-phase flow, heat transfer, solute transport, and rock deformation to liquid flow are also important. For stochastic modeling of alternating units of welded and nonwelded tuff or formations bounded by fault zones, correlations and constraints on average values of saturated permeability and air entry scaling factor between different units need to be imposed to avoid unlikely combinations of parameters and predictions. Large-scale simulations require efficient and verifiable numerical algorithms. New path integration approaches based on postulates of minimum work and mass conservation to solve flow geometry and potential distribution simultaneously are introduced. This verifiable integral approach, together with fractal scaling procedures to generate statistical realizations with parameter distribution, correlation, and scaling taken into account, can be used to quantify uncertainties and generate the cumulative distribution function for groundwater travel times.
Wang, J.S.Y.; Narasimhan, T.N. [Lawrence Berkeley Lab., CA (United States)
Direct coupling of a genome-scale microbial in silico model and a groundwater reactive transport model
The activity of microorganisms often plays an important role in dynamic natural attenuation or engineered bioremediation of subsurface contaminants, such as chlorinated solvents, metals, and radionuclides. To evaluate and/or design bioremediated systems, quantitative reactive transport models are needed. State-of-the-art reactive transport models often ignore the microbial effects or simulate the microbial effects with static growth yield and constant reaction rate parameters over simulated conditions, while in reality microorganisms can dynamically modify their functionality (such as utilization of alternative respiratory pathways) in response to spatial and temporal variations in environmental conditions. Constraint-based genome-scale microbial in silico models, using genomic data and multiple-pathway reaction networks, have been shown to be able to simulate transient metabolism of some well studied microorganisms and identify growth rate, substrate uptake rates, and byproduct rates under different growth conditions. These rates can be identified and used to replace specific microbially-mediated reaction rates in a reactive transport model using local geochemical conditions as constraints. We previously demonstrated the potential utility of integrating a constraint based microbial metabolism model with a reactive transport simulator as applied to bioremediation of uranium in groundwater. However, that work relied on an indirect coupling approach that was effective for initial demonstration but may not be extensible to more complex problems that are of significant interest (e.g., communities of microbial species, multiple constraining variables). Here, we extend that work by presenting and demonstrating a method of directly integrating a reactive transport model (FORTRAN code) with constraint-based in silico models solved with IBM ILOG CPLEX linear optimizer base system (C library). The models were integrated with BABEL, a language interoperability tool. The modeling system is designed in such a way that constraint-based models targeting different microorganisms or competing organism communities can be easily plugged into the system. Constraint-based modeling is very costly given the size of a genome-scale reaction network. To save computation time, a binary tree is traversed to examine the concentration and solution pool generated during the simulation in order to decide whether the constraint-based model should be called. We also show preliminary results from the integrated model including a comparison of the direct and indirect coupling approaches.
Fang, Yilin; Scheibe, Timothy D.; Mahadevan, Radhakrishnan; Garg, Srinath; Long, Philip E.; Lovley, Derek R.
Nonlinear elasto-plastic model for dense granular flow
This work proposes a model for granular deformation that predicts the stress and velocity profiles in well-developed dense granular flows. Recent models for granular elasticity (Jiang and Liu 2003) and rate-sensitive plastic flow (Jop et al. 2006) are reformulated and combined into one universal granular continuum law, capable of predicting flowing regions and stagnant zones simultaneously in any arbitrary 3D flow geometry. The unification is performed by justifying and implementing a Kroner-Lee elasto-plastic decomposition, with care taken to ensure certain continuum physical principles are necessarily upheld. The model is then numerically implemented in multiple geometries and results are compared to experiments and discrete simulations.
Ken Kamrin
Technologies Program Office Program Manager: Mr. Gurpreet Singh Petrodiesel vs. Biodiesel 2 Primary Breakup Inner Nozzle Flow Influence of Physical and Chemical properties of...
REYNOLDS STRESS MODEL IMPLEMENTATION FOR HYPERSONIC FLOW SIMULATIONS Arianna Bosco, PhD student, 52056 Aachen, Germany Abstract The simulation of hypersonic flows presents some difficulties due of the model is analyzed. 1 Introduction The aerodynamic design of hypersonic inlets is a criti- cal issue
A phenomenological model for the flow resistance over submerged vegetation
A phenomenological model for the flow resistance over submerged vegetation Alexandra G. Konings,1: Konings, A. G., G. G. Katul, and S. E. Thompson (2012), A phenomenological model for the flow resistance [2002]. In this paper, a phenomenological approach is used to describe the momentum transfer
Katul, Gabriel
Solyndra Facts vs. Fiction: Cash Flow Modeling
Broader source: Energy.gov [DOE]
Questions have been raised about a quote selectively pulled from an Aug. 20, 2009 email to make it look like Solyndra would run out of cash by Sept. 2011. To be clear, the analysis addressed in that email did not refer to Solyndra�s corporate cash flow, but rather the cash flow for a subsidiary of Solyndra � the �Fab 2 Project Company.
Theoretical foundation for measuring the groundwater age distribution.
In this study, we use PFLOTRAN, a highly scalable, parallel, flow and reactive transport code to simulate the concentrations of 3H, 3He, CFC-11, CFC-12, CFC-113, SF6, 39Ar, 81Kr, 4He and themean groundwater age in heterogeneous fields on grids with an excess of 10 million nodes. We utilize this computational platform to simulate the concentration of multiple tracers in high-resolution, heterogeneous 2-D and 3-D domains, and calculate tracer-derived ages. Tracer-derived ages show systematic biases toward younger ages when the groundwater age distribution contains water older than the maximum tracer age. The deviation of the tracer-derived age distribution from the true groundwater age distribution increases with increasing heterogeneity of the system. However, the effect of heterogeneity is diminished as the mean travel time gets closer the tracer age limit. Age distributions in 3-D domains differ significantly from 2-D domains. 3D simulations show decreased mean age, and less variance in age distribution for identical heterogeneity statistics. High-performance computing allows for investigation of tracer and groundwater age systematics in high-resolution domains, providing a platform for understanding and utilizing environmental tracer and groundwater age information in heterogeneous 3-D systems. Groundwater environmental tracers can provide important constraints for the calibration of groundwater flow models. Direct simulation of environmental tracer concentrations in models has the additional advantage of avoiding assumptions associated with using calculated groundwater age values. This study quantifies model uncertainty reduction resulting from the addition of environmental tracer concentration data. The analysis uses a synthetic heterogeneous aquifer and the calibration of a flow and transport model using the pilot point method. Results indicate a significant reduction in the uncertainty in permeability with the addition of environmental tracer data, relative to the use of hydraulic measurements alone. Anthropogenic tracers and their decay products, such as CFC11, 3H, and 3He, provide significant constraint oninput permeability values in the model. Tracer data for 39Ar provide even more complete information on the heterogeneity of permeability and variability in the flow system than the anthropogenic tracers, leading to greater parameter uncertainty reduction.
Gardner, William Payton; Arnold, Bill Walter
Data-flow graphs as a model of parallel complexity
A new model of parallel computation based on data-flow graphs is introduced, which is specifically oriented towards complexity theory. Data-flow graphs are capable of illustrating properties of synchronous, asynchronous, and nondeterministic computations. Sufficient conditions are derived for asynchronous data-flow graphs to be determinate, i.e., all possible computations are finite and yield the same result. For determinate graphs, it is shown that the synchronous computation is as fast as any asynchronous computation. An algorithm is presented that transforms a nondeterminate data-flow graphs into a synchronous determinate one. The basic data-flow graph idea is extended into a model with greater potential parallelism, called the Uniform Data Flow Graph Family (UDFGF) Model. It is proved that time and space for the UDFGF model are polynomially related to reversal and space for the Turing Machine model, in both the deterministic and nondeterministic cases. In addition to forming an abstract computational model, data-flow graphs are parallel programs for real multiprocessors. Given a data flow graph program and a multiprocessor, each node of the graph must be assigned to one of the processors. It is proved that this problem is intractable, and a practical algorithm to find approximate solutions for it is presented.
Campbell, M.L.
Shearing Flows in Liquid Crystal Models
The liquid crystal phase is a phase of matter between the solid and liquid phase whose flow is characterized by a velocity field and a director field which describes locally the orientation of the liquid crystal. In this ...
Dorn, Timothy
Coupled multiphase flow and poromechanics: A computational model of pore pressure effects on fault slip and earthquake triggering
The coupling between subsurface flow and geomechanical deformation is critical in the assessment of the environmental impacts of groundwater use, underground liquid waste disposal, geologic storage of carbon dioxide, and ...
Jha, Birendra
Generating expansion model incorporating compact DC power flow equations
This paper presents a compact method of incorporating the spatial dimension into the generation expansion problem. Compact DC power flow equations are used to provide real-power flow coordination equations. Using these equations the marginal contribution of a generator to th total system loss is formulated as a function of that generator`s output. Incorporating these flow equations directly into the MIP formulation of the generator expansion problem results in a model that captures a generator`s true net marginal cost, one that includes both the cost of generation and the cost of transport. This method contrasts with other methods that iterate between a generator expansion model and an optimal power flow model. The proposed model is very compact and has very good convergence performance. A case study with data from Kenya is used to provide a practical application to the model.
Nderitu, D.G.; Sparrow, F.T.; Yu, Z. [Purdue Inst. for Interdisciplinary Engineering Studies, West Lafayette, IN (United States)
1 MATHEMATICAL MODELING AND SIMULATION FOR FLUID FLOW IN POROUS MEDIA Ewing, Richard Texas A is to understand the complex chemical, physical, and fluid flow processes occurring in an underground porous medium with one pass through these four steps. Once a computer code has been developed which gives concrete
Scaling up and modeling for transport and flow
& modélisation des écoulements de fluides en milieux poreux DUBROVNIK, CROATIA 13-16 OCTOBER 2008 BOOK for Transport and Flow in Porous Media Dubrovnik, Croatia, 13-16 October 2008 Book of abstracts #12;Contents and Modeling for Transport and Flow in Porous Media, held at Dubrovnik, Croatia, 1316 October 2008
Rogina, Mladen
Submarine landslide flows simulation through centrifuge modelling
) ........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 2.7: Failure at Helsinki Harbour , Finland in 1936 (after Andresen and Bjerrum, 1967... ) ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 2.18: Energy conversion for debris flows (modified after Iverson, 1997) .......................................................................................... 50 Figure 2.19: Schematic cross-section defini ng H...
Gue, Chang Shin
Modelling macroeconomic flows related to large ensembles
, including, say, oil prices, interest rates, etc; dynamics of shares markets are governed by information are illustrated by flows of a liquid between interconnected reservoirs, where the heights of different reservoirs is changing with time, and movement of the liquid between the reservoirs is governed by gravity, see Figure 1
Schellekens, Michel P.
A turbulence model for buoyant flows based on vorticity generation.
A turbulence model for buoyant flows has been developed in the context of a k-{var_epsilon} turbulence modeling approach. A production term is added to the turbulent kinetic energy equation based on dimensional reasoning using an appropriate time scale for buoyancy-induced turbulence taken from the vorticity conservation equation. The resulting turbulence model is calibrated against far field helium-air spread rate data, and validated with near source, strongly buoyant helium plume data sets. This model is more numerically stable and gives better predictions over a much broader range of mesh densities than the standard k-{var_epsilon} model for these strongly buoyant flows.
Domino, Stefan Paul; Nicolette, Vernon F.; O'Hern, Timothy John; Tieszen, Sheldon R.; Black, Amalia Rebecca
Modeling and design of semi-solid flow batteries
A three-dimensional dynamic model of the recently introduced semi-solid flow battery system is developed and applied to address issues with important design and operation implications. Because of the high viscosity of ...
Brunini, Victor Eric
Can We Accurately Model Fluid Flow in Shale?
2013 00:00 Over 20 trillion cubic meters of natural gas are trapped in shale, but many shale oil and gas producers still use models of underground fluid flow that date back to...
Hanford Site ground-water monitoring for 1993
This report presents the results of the Ground-Water Surveillance Project monitoring for calendar year 1993 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiological and chemical waste that have impacted ground-water quality on the Site. Monitoring of water levels and ground-water chemistry is performed to track the extent of contamination and trends in contaminant concentrations. The 1993 monitoring was also designed to identify emerging ground-water quality problems. The information obtained is used to verify compliance with applicable environmental regulations and to evaluate remedial actions. Data from other monitoring and characterization programs were incorporated to provide an integrated assessment of Site ground-water quality. Additional characterization of the Site`s geologic setting and hydrology was performed to support the interpretation of contaminant distributions. Numerical modeling of sitewide ground-water flow also supported the overall project goals. Water-level monitoring was performed to evaluate ground-water flow directions, to track changes in water levels, and to relate such changes to changes in site disposal practices. Water levels over most of the Hanford Site continued to decline between June 1992 and June 1993. The greatest declines occurred in the 200-West Area. These declines are part of the continued response to the cessation of discharge to U Pond and other disposal facilities. The low permeability in this area which enhanced mounding of waste-water discharge has also slowed the response to the reduction of disposal. Water levels remained nearly constant in the vicinity of B Pond, as a result of continued disposal to the pond. Water levels measured from wells in the unconfined aquifer north and east of the Columbia River indicate that the primary source of recharge is irrigation practices.
Dresel, P.E.; Luttrell, S.P.; Evans, J.C. [and others
On the spatial nature of the groundwater pumping externality
On the spatial nature of the groundwater pumping externality Nicholas Brozovic´ a, *, David L and instantly to groundwater pumping. In this paper, we develop an economic model of groundwater manage- ment the magnitude of the groundwater pumping externality relative to spatially explicit models. In particular
Sunding, David
GROUNDWATER DATA REQUIREMENT AND ANALYSIS C. P. Kumar
.0 INTRODUCTION Groundwater is used for a variety of purposes, including irrigation, drinking, and manufacturing characteristics of groundwater. Numerical models are capable of solving large and complex groundwater problems/monitoring of required data form an integral part of any groundwater modelling exercise. 2.0 DATA REQUIREMENT
Preliminary conceptual study on impact of land reclamation on groundwater flow and contaminant migration in Penny's Bay
but will migrate northeast toward Yam O Wan. FEMWATER, a three-dimensional finite element ground water model
Jiao, Jiu Jimmy
unconfined aquifer that consists mainly of unconsolidated to cemented deposits of clay, silt, sand, and gravel. Measures of saturated thickness (ST) assume that all saturated deposits contribute water to pumping wells equally. However, fine...-grained sediments like clay and silt, as well as locally cemented zones, form low permeability units that impede ground-water flow (Gutentag et al., 1981; Macfarlane and Wilson, 2006; Macfarlane, 2009). In southwest Kansas, unconsolidated sand and gravel deposits...
Kreitzer, Sarah R.
Nonlocal and localized analyses of conditional mean transient flow in bounded, randomly heterogeneous
TERMS: 1829 Hydrology: Groundwater hydrology; 1869 Hydrology: Stochastic processes; 3210 Mathematical Geophysics: Modeling; 3230 Mathematical Geophysics: Numerical solutions; KEYWORDS: transient flow.1029/2003WR002099. 1. Introduction [2] Hydraulic parameters vary randomly in space and are therefore often
Tartakovsky, Daniel M.
E-Print Network 3.0 - air flow models Sample Search Results
Institute of Aeronautics and Astronautics Numerical Modeling of Doorway Flow Summary: software. The problem that was modeled is that of a flow from an air curtain mounted...
Modelling of multiphase flow in ironmaking blast furnace
A mathematical model for the four-phase (gas, powder, liquid, and solids) flow in a two-dimensional ironmaking blast furnace is presented by extending the existing two-fluid flow models. The model describes the motion of gas, solid, and powder phases, based on the continuum approach, and implements the so-called force balance model for the flow of liquids, such as metal and slag in a blast furnace. The model results demonstrate a solid stagnant zone and dense powder hold-up region, as well as a dense liquid flow region that exists in the lower part of a blast furnace, which are consistent with the experimental observations reported in the literature. The simulation is extended to investigate the effects of packing properties and operational conditions on the flow and the volume fraction distribution of each phase in a blast furnace. It is found that solid movement has a significant effect on powder holdup distribution. Small solid particles and low porosity distribution are predicted to affect the fluid flow considerably, and this can cause deterioration in bed permeability. The dynamic powder holdup in a furnace increases significantly with the increase of powder diameter. The findings should be useful to better understand and control blast furnace operations.
Dong, X.F.; Yu, A.B.; Burgess, J.M.; Pinson, D.; Chew, S.; Zulli, P. [University of New South Wales, Sydney, NSW (Australia). School for Material Science and Engineering
Fluid flow near reservoir lakes inferred from the spatial and temporal analysis of the electric potential
, 2002. 1. Introduction [2] Detecting subsurface groundwater circulation using geophysical methods to result from the electrokinetic coupling associated with a vertical groundwater flow connecting a constant pore pressure source to the bottom of the lakes. Numerical modeling indicates that the spatial
Adolphs, Ralph
Field site investigation: Effect of mine seismicity on groundwater hydrology
The results of a field investigation on the groundwater-hydrologic effect of mining-induced earthquakes are presented in this report. The investigation was conducted at the Lucky Friday Mine, a silver-lead-zinc mine in the Coeur d`Alene Mining District of Idaho. The groundwater pressure in sections of three fracture zones beneath the water table was monitored over a 24-mo period. The fracture zones were accessed through a 360-m-long inclined borehole, drilled from the 5,700 level station of the mine. The magnitude, source location, and associated ground motions of mining-induced seismic events were also monitored during the same period, using an existing seismic instrumentation network for the mine, augmented with additional instruments installed specifically for the project by the center for Nuclear Waste Regulatory Analyses (CNWRA). More than 50 seismic events of Richter magnitude 1.0 or larger occurred during the monitoring period. Several of these events caused the groundwater pressure to increase, whereas a few caused it to decrease. Generally, the groundwater pressure increased as the magnitude of seismic event increased; for an event of a given magnitude, the groundwater pressure increased by a smaller amount as the distance of the observation point from the source of the event increased. The data was examined using regression analysis. Based on these results, it is suggested that the effect of earthquakes on groundwater flow may be better understood through mechanistic modeling. The mechanical processes and material behavior that would need to be incorporated in such a model are examined. They include a description of the effect of stress change on the permeability and water storage capacity of a fracture rock mass; transient fluid flow; and the generation and transmission of seismic waves through the rock mass.
Ofoegbu, G.I.; Hsiung, S.; Chowdhury, A.H. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses; Philip, J. [Nuclear Regulatory Commission, Washington, DC (United States)
Fuzzy modelling of power system optimal load flow
In this paper, a fuzzy model for power system operation is presented. Uncertainties in loads and generations are modeled as fuzzy numbers. System behavior under known (while uncertain) injections is dealt with by a DC fuzzy power flow model. System optimal (while uncertain) operation is calculated with linear programming procedures where the problem nature and structure allows some efficient techniques such as Dantzig Wolfe decomposition and dual simplex to be used. Among the results, one obtains a fuzzy cost value for system operation and possibility distributions for branch power flows and power generations. Some risk analysis is possible, as system robustness and exposure indices can be derived and hedging policies can be investigated.
Miranda, V.; Saraiva, J.T. (FEUP, DEEC, Faculdade de Engenharia da Univ. do Porto, INESC, Inst. de Engenharia de Sistemas e Computadores, Lg de Mompilher 4000 Porto (PT))
A distributed converging overland flow model: 1. Mathematical solutions
MODEL The kinematic wave equations of continuity and momentum for a converging section are [Singh, 1974] 889 890 SHERMAN AND SINGH: FLOW MODELING, 1 X Fig. 1. Geometry of converging overland flow model. Oh O(uh) uh Ot q- Ox - q(x, t) q- L -- x (3...)' Q = uh = a(x,t)h n (4) where L is the length of the converging section (Figure 1). For a specified rainfall duration T, q(x, t) = 0 when t > T. We assume that n > 1. Eliminating u in (3) and (4), .we get Oh q_ na(x t)h \\"- Oh Ot ' Ox a(x, t...
Sherman, Bernard; Singh, Vijay P.
Phenomenological model for ordered onions under shear flow
We propose a phenomenological model for the multi-lamellar vesicles (onions) formation induced by shear flow. In a nonionic surfactant (C$_{12}$E$_4$) system, onion phases under a fixed shear flow within a certain range show the order-disorder transition accompanied with a size jump by changing temperature. Our model can simulate ordered and disordered onion phases with different onion sizes. We show numerical results of the onion formation simulated by the model and also discuss what factors in this system are critical to cause the transition between these two different onion phases.
Kenta Odagiri; Kazue Kudo
Cost and Performance Model for Redox Flow Batteries
A cost model was developed for all vanadium and iron-vanadium redox flow batteries. Electrochemical performance modeling was done to estimate stack performance at various power densities as a function of state of charge. This was supplemented with a shunt current model and a pumping loss model to estimate actual system efficiency. The operating parameters such as power density, flow rates and design parameters such as electrode aspect ratio, electrolyte flow channel dimensions were adjusted to maximize efficiency and minimize capital costs. Detailed cost estimates were obtained from various vendors to calculate cost estimates for present, realistic and optimistic scenarios. The main drivers for cost reduction for various chemistries were identified as a function of the energy to power ratio of the storage system. Levelized cost analysis further guided suitability of various chemistries for different applications.
Viswanathan, Vilayanur V.; Crawford, Aladsair J.; Stephenson, David E.; Kim, Soowhan; Wang, Wei; Li, Bin; Coffey, Greg W.; Thomsen, Edwin C.; Graff, Gordon L.; Balducci, Patrick J.; Kintner-Meyer, Michael CW; Sprenkle, Vincent L.
Wetting and free surface flow modeling for potting and encapsulation.
As part of an effort to reduce costs and improve quality control in encapsulation and potting processes the Technology Initiative Project ''Defect Free Manufacturing and Assembly'' has completed a computational modeling study of flows representative of those seen in these processes. Flow solutions are obtained using a coupled, finite-element-based, numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorithm. This approach incorporates novel methods for representing surface tension and wetting forces that affect the evolution of the free surface. In addition, two commercially available codes, ProCAST and MOLDFLOW, are also used on geometries representing encapsulation processes at the Kansas City Plant. Visual observations of the flow in several geometries are recorded in the laboratory and compared to the models. Wetting properties for the materials in these experiments are measured using a unique flowthrough goniometer.
Brooks, Carlton, F.; Brooks, Michael J. (Los Alamos National Laboratory, Los Alamos, NM); Graham, Alan Lyman (Los Alamos National Laboratory, Los Alamos, NM); Noble, David F. (David Frederick) (.; )); Notz, Patrick K.; Hopkins, Matthew Morgan; Castaneda, Jaime N.; Mahoney, Leo James (Kansas City Plant, Kansas City, MO); Baer, Thomas A.; Berchtold, Kathryn (Los Alamos National Laboratory, Los Alamos, NM); Adolf, Douglas Brian; Wilkes, Edward Dean; Rao, Rekha Ranjana; Givler, Richard C.; Sun, Amy Cha-Tien; Cote, Raymond O.; Mondy, Lisa Ann; Grillet, Anne Mary; Kraynik, Andrew Michael
A Model For Syn-Eruptive Groundwater Flow During The Phreatoplinian...
Open Energy Info (EERE)
phreatoplinian activity is not obvious because eyewitness records rule out snow, surface water, and heavy rainfall. Hence we use 3D numerical simulations of the syn-eruptive...
A Model For Syn-Eruptive Groundwater Flow During The Phreatoplinian Phase
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160 East 300 SouthWater Rights, Substantive(Sichuan, Sw China)| OpenTheOf The 28-29 March
alpine karst groundwater: Topics by E-print Network
2 Hydrochemistry, a tool for understanding karst groundwater flows Jacques MUDRY, Chrono-Environment laboratory Physics Websites Summary: Hydrochemistry, a tool for understanding...
Numerical modeling of an all vanadium redox flow battery.
We develop a capability to simulate reduction-oxidation (redox) flow batteries in the Sierra Multi-Mechanics code base. Specifically, we focus on all-vanadium redox flow batteries; however, the capability is general in implementation and could be adopted to other chemistries. The electrochemical and porous flow models follow those developed in the recent publication by [28]. We review the model implemented in this work and its assumptions, and we show several verification cases including a binary electrolyte, and a battery half-cell. Then, we compare our model implementation with the experimental results shown in [28], with good agreement seen. Next, a sensitivity study is conducted for the major model parameters, which is beneficial in targeting specific features of the redox flow cell for improvement. Lastly, we simulate a three-dimensional version of the flow cell to determine the impact of plenum channels on the performance of the cell. Such channels are frequently seen in experimental designs where the current collector plates are borrowed from fuel cell designs. These designs use a serpentine channel etched into a solid collector plate.
Clausen, Jonathan R.; Brunini, Victor E.; Moffat, Harry K.; Martinez, Mario J.
An Integrated Modeling Analysis of Unsaturated Flow Patterns in Fractured Rock
study, heat flow simulations use a 3-D thermal model grid (model grid, which is used for gas flow and ambient heat-flowgrid showing a smaller model domain, used for modeling gas and heat
Wu, Yu-Shu; Lu, Guoping; Zhang, Keni; Pan, Lehua; Bodvarsson, Gudmundur S.
Modelling Inter-Industry Material Flows
............................................................................................ 4 3.1.2. Life-cycle Analysis. The development of energy-materials-economic models arose out of the need for tools to aid the development, capable of representing complex systems and interactions in a comprehensive and concise way. However
Numerical methods for the simulation of salt migration in regional groundwater
Numerical methods for the simulation of salt migration in regional groundwater flow E.S. van Baaren #12;Contents 1 Introduction 1 2 Model description 3 2.1 Basic Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.2 Finite Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3.2.1 Grid
Geothermal loan guaranty cash flow model: description and users' manual
This is the users guide for the Geothermal Loan Guaranty Cash Flow Model (GCFM). GCFM is a Fortran code which designs and costs geothermal fields and electric power plants. It contains a financial analysis module which performs life cycle costing analysis taking into account various types of taxes, costs and financial structures. The financial module includes a discounted cash flow feature which calculates a levelized breakeven price for each run. The user's guide contains descriptions of the data requirements and instructions for using the model.
Keimig, M.A.; Rosenberg, J.I.; Entingh, D.J.
Design verification and cold-flow modeling test report
This report presents a compilation of the following three test reports prepared by TRW for Alaska Industrial Development and Export Authority (AIDEA) as part of the Healy Clean Coal Project, Phase 1 Design of the TRW Combustor and Auxiliary Systems, which is co-sponsored by the Department of Energy under the Clean Coal Technology 3 Program: (1) Design Verification Test Report, dated April 1993, (2) Combustor Cold Flow Model Report, dated August 28, 1992, (3) Coal Feed System Cold Flow Model Report, October 28, 1992. In this compilation, these three reports are included in one volume consisting of three parts, and TRW proprietary information has been excluded.
Not Available
Multiphase Flow Modeling of Biofuel Production Processes
As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.
D. Gaston; D. P. Guillen; J. Tester
Variably Saturated Flow and Multicomponent Biogeochemical Reactive Transport Modeling of a Uranium Bioremediation Field Experiment
Field experiments at a former uranium mill tailings site have identified the potential for stimulating indigenous bacteria to catalyze the conversion of aqueous uranium in the +6 oxidation state to immobile solid-associated uranium in the +4 oxidation state. This effectively removes uranium from solution resulting in groundwater concentrations below actionable standards. Three-dimensional, coupled variably-saturated flow and biogeochemical reactive transport modeling of a 2008 in situ uranium bioremediation field experiment is used to better understand the interplay of transport rates and biogeochemical reaction rates that determine the location and magnitude of key reaction products. A comprehensive reaction network, developed largely through previous 1-D modeling studies, was used to simulate the impacts on uranium behavior of pulsed acetate amendment, seasonal water table variation, spatially-variable physical (hydraulic conductivity, porosity) and geochemical (reactive surface area) material properties. A principal challenge is the mechanistic representation of biologically-mediated terminal electron acceptor process (TEAP) reactions whose products significantly alter geochemical controls on uranium mobility through increases in pH, alkalinity, exchangeable cations, and highly reactive reduction products. In general, these simulations of the 2008 Big Rusty acetate biostimulation field experiment in Rifle, Colorado confirmed previously identified behaviors including (1) initial dominance by iron reducing bacteria that concomitantly reduce aqueous U(VI), (2) sulfate reducing bacteria that become dominant after {approx}30 days and outcompete iron reducers for the acetate electron donor, (3) continuing iron-reducer activity and U(VI) bioreduction during dominantly sulfate reducing conditions, and (4) lower apparent U(VI) removal from groundwater during dominantly sulfate reducing conditions. New knowledge on simultaneously active metal and sulfate reducers has been incorporated into the modeling. In this case, an initially small population of slow growing sulfate reducers is active from the initiation of biostimulation. Three-dimensional, variably saturated flow modeling was used to address impacts of a falling water table during acetate injection. These impacts included a significant reduction in aquifer saturated thickness and isolation of residual reactants and products, as well as unmitigated uranium, in the newly unsaturated vadose zone. High permeability sandy gravel structures resulted in locally high flow rates in the vicinity of injection wells that increased acetate dilution. In downgradient locations, these structures created preferential flow paths for acetate delivery that enhanced local zones of TEAP reactivity and subsidiary reactions. Conversely, smaller transport rates associated with the lower permeability lithofacies (e.g., fine) and vadose zone were shown to limit acetate access and reaction. Once accessed by acetate, however, these same zones limited subsequent acetate dilution and provided longer residence times that resulted in higher concentrations of TEAP products when terminal electron donors and acceptors were not limiting. Finally, facies-based porosity and reactive surface area variations were shown to affect aqueous uranium concentration distributions; however, the ranges were sufficiently small to preserve general trends. Large computer memory and high computational performance were required to simulate the detailed coupled process models for multiple biogeochemical components in highly resolved heterogeneous materials for the 110-day field experiment and 50 days of post-biostimulation behavior. In this case, a highly-scalable subsurface simulator operating on 128 processor cores for 12 hours was used to simulate each realization. An equivalent simulation without parallel processing would have taken 60 days, assuming sufficient memory was available.
Yabusaki, Steven B.; Fang, Yilin; Williams, Kenneth H.; Murray, Christopher J.; Ward, Anderson L.; Dayvault, Richard; Waichler, Scott R.; Newcomer, Darrell R.; Spane, Frank A.; Long, Philip E.
Toward a new paradigm for reactive flow modeling.
Traditional reactive flow modeling provides a computational representation of shock initiation of energetic materials. Most reactive flow models require ad hoc assumptions to obtain robust simulations, assumptions that result from partitioning energy and volume change between constituents in a reactive mixture. For example, most models assume pressure and/or temperature equilibrium for the mixture. Many mechanical insults to energetic materials violate these approximations. Careful analysis is required to ensure that the model assumptions and limitations are not exceeded. One limitation is that the shock to detonation transition is replicated only for strong planar shocks. Many models require different parameters to match data from thin pulse, ramp wave, or multidimensional loading, an approach that fails for complex loading. To accurately simulate reaction under non-planar shock impact scenarios a new formalism is required. The continuum mixture theory developed by Baer and Nunziato is used to eliminate ad hoc assumptions and limitations of current reactive flow models. This modeling paradigm represents the multiphase nature of reacting condensed/gas mixtures. Comparisons between simulations and data are presented.
Schmitt, Robert Gerard
Plastic flow modeling in glassy polymers
Glassy amorphous and semi-crystalline polymers exhibit strong rate, temperature, and pressure dependent polymeric yield. As a rule of thumb, in uniaxial compression experiments the yield stress increases with the loading rate and applied pressure, and decreases as the temperature increases. Moreover, by varying the loading state itself complex yield behavior can be observed. One example that illustrates this complexity is that most polymers in their glassy regimes (i.e., when the temperature is below their characteristic glass transition temperature) exhibit very pronounced yield in their uniaxial stress stress-strain response but very nebulous yield in their uniaxial strain response. In uniaxial compression, a prototypical glassy-polymer stress-strain curve has a stress plateau, often followed by softening, and upon further straining, a hardening response. Uniaxial compression experiments of this type are typically done from rates of 10{sup -5} s{sup -1} up to about 1 s{sup -1}. At still higher rates, say at several thousands per second as determined from Split Hopkinson Pressure Bar experiments, the yield can again be measured and is consistent with the above rule of thumb. One might expect that that these two sets of experiments should allow for a successful extrapolation to yet higher rates. A standard means to probe high rates (on the order of 105-107 S-I) is to use a uniaxial strain plate impact experiment. It is well known that in plate impact experiments on metals that the yield stress is manifested in a well-defined Hugoniot Elastic Limit (HEL). In contrast however, when plate impact experiments are done on glassy polymers, the HEL is arguably not observed, let alone observed at the stress estimated by extrapolating from the lower strain rate experiments. One might argue that polymer yield is still active but somehow masked by the experiment. After reviewing relevant experiments, we attempt to address this issue. We begin by first presenting our recently developed glassy polymer model. While polymers are well known for their non-equilibrium deviatoric behavior we have found the need for incorporating both equilibrium and non-equilibrium volumetric behavior into our theory. Experimental evidence supporting the notion of non-equilibrium volumetric behavior will be summarized. Our polymer yield model accurately captures the stress plateau, softening and hardening and its yield stress predictions agree well with measured values for several glassy polymers including PMMA, PC, and an epoxy resin. We then apply our theory to plate impact experiments in an attempt to address the questions associated with high rate polymer yield in uniaxial strain configurations.
Clements, Brad [Los Alamos National Laboratory
Introduction Application of numerical models of ground water flow
(Portniaguine and Solomon 1998), and ground water temperature (Doussan et al. 1994). Compared to calibration depended on calibration methodology; models calibrated with multiple targets simulated q more accurately of Calibration Methodology on Ground Water Flow Predictions by James E. Saiers1, David P. Genereux2, and Carl H
Saiers, James
Computational methods for several models of ice stream flow
on any grid Shallow ice approximation produces oscillatory solutions Nonlinear and linear solvers haveComputational methods for several models of ice stream flow Jed Brown Laboratory of Hydrology transition at ice stream margins Bed slope is discontinuous and of order 1. Taylor expansions no longer valid
Brown, Jed
concretes such as Self-Compacting Concrete (SCC) tools for prediction of the form filling of SCC are neededCOMPUTATIONAL MODELING OF CONCRETE FLOW: STATE OF THE ART Nicolas Roussel Laboratoire Central des Lars N. Thrane Concrete Centre, Danish Technological Institute Peter Szabo Department of Chemical
A multiple temperature kinetic model and its application to micro-scale gas flow simulations
A multiple temperature kinetic model and its application to micro-scale gas flow simulations model, micro-scale flows. 1. Introduction Gas flows can be classified according to the flow email@example.com Abstract This paper presents a numerical approach to solve the multiple temperature kinetic model (MTKM
Xu, Kun
Semi-distributed lumped model of a karst system under active1 management2
system27 28 Keywords29 Impulse response30 Groundwater flow modeling31 Groundwater level fluctuations32 Pumping33 Introduction34 Numerical models for karst aquifers usually fall within two main categories1 Semi-distributed lumped model of a karst system under active1 management2 Bernard LADOUCHE1
Modeling for Free Surface Flow with Phase Change
The development of predictive capability for free surface flow with phase change is essential to evaluate liquid wall protection schemes for various fusion chambers in IFE and MFE. This paper presents a numerical methodology for free surface flow with heat and mass transfer to help resolve feasibility issues encountered in the aforementioned fusion engineering fields. The numerical methodology is conducted within the framework of the incompressible flow with the heat and mass transfer model. We present a new second-order projection method, in conjunction with Approximate-Factorization techniques (AF method) for incompressible Navier-Stokes equations. The level set method was used to capture the free surface of the flow and the deformation of the droplets accurately. This numerical investigation identifies the physics characterizing transient heat and mass transfer of the droplet and the free surface flow. The preliminary results show that the numerical methodology is successful in modeling the free surface with heat and mass transfer, though some severe deformation such as breaking and merging occurs. The versatility of the numerical methodology shows that the work can easily handle complex physical conditions in fusion science and engineering.
Luo Xiaoyong; Ni Mingjiu; Ying, Alice; Abdou, M. [University of California, Los Angeles (United States)
Analyzing flow patterns in unsaturated fractured rock of Yucca Mountain using an integrated modeling approach
heat flow simulations use the 3-D thermal model grid (Figuremodel grid, which is used for gas flow and ambient heat flowgrid showing a smaller model domain, used for modeling gas and heat
Imaging, Characterizing, and Modeling of Fracture Networks and Fluid Flow in EGS Reservoirs
Project objectives: Improve image resolution for microseismicimaging and time-lapse active seismic imaging; Enhance the prediction of fluid flow and temperature distributions and stress changes by coupling fracture flow simulations with reservoir flow simulations; and integrating imaging into modeling.
k - Version of Finite Element Method for Polymer flows using Giesekus Constitutive Model
and hence high Deborah number flows are invariably associated with higher flow rates and thus higher velocities. In many standard model problems such as couette flow, lid driven cavity, expansion, contraction etc, severe deborah number (De) limitations...
Deshpande, Kedar M.
Simulation of High Density Pedestrian Flow: Microscopic Model
In recent years modelling crowd and evacuation dynamics has become very important, with increasing huge numbers of people gathering around the world for many reasons and events. The fact that our global population grows dramatically every year and the current public transport systems are able to transport large amounts of people, heightens the risk of crowd panic or crush. Pedestrian models are based on macroscopic or microscopic behaviour. In this paper, we are interested in developing models that can be used for evacuation control strategies. This model will be based on microscopic pedestrian simulation models, and its evolution and design requires a lot of information and data. The people stream will be simulated, based on mathematical models derived from empirical data about pedestrian flows. This model is developed from image data bases, so called empirical data, taken from a video camera or data obtained using human detectors. We consider the individuals as autonomous particles interacting through socia...
Dridi, Mohamed H
Multiple temperature kinetic model and gas-kinetic method for hypersonic non-equilibrium flow computations
Multiple temperature kinetic model and gas-kinetic method for hypersonic non-equilibrium flow. For the non-equilibrium flow computations, i.e., the nozzle flow and hypersonic rarefied flow over flat plate-kinetic method; Hypersonic and rarefied flows 1. Introduction The development of aerospace technology has
A nuclear data acquisition system flow control model
A general Petri Net representation of a nuclear data acquisition system model is presented. This model provides for the unique requirements of a nuclear data acquisition system including the capabilities of concurrently acquiring asynchronous and synchronous data, of providing multiple priority levels of flow control arbitration, and of permitting multiple input sources to reside at the same priority without the problem of channel lockout caused by a high rate data source. Finally, a previously implemented gamma camera/physiological signal data acquisition system is described using the models presented.
Hack, S.N.
Numerical simulation of ground-water flow in the Culebra dolomite at the Waste Isolation Pilot Plant (WIPP) site: Second interim report
This hydrogeologic modeling study has been performed as part of the regional hydrologic characterization of the Waste Isolation Pilot Plant (WIPP) Site in southeastern New Mexico. The study resulted in an estimation of the transmissivity distrubution, hydraulic potentials, flow field, and fluid densities in the Culebra Dolomite Member of the Permian Rustler Formation at the WIPP site. The three-dimensional finite-difference code SWIFT-II was employed for the numerical modeling, using variable-fluid-density and a single-porosity formulation. The modeled area includes and extends beyond the WIPP controlled zone (Zone 3). The work performed consisted of modeling the hydrogeology of the Culebra using two approaches: (1) steady-state modeling to develop the best estimate of the undisturbed head distribution, i.e., of the situation before sinking if the WIPP shafts, which began in 1981; and (2) superimposed transient modeling of local hydrologic responses to excavation of the three WIPP shafts at the center of the WIPP site, as well as to various well tests. Boundary conditions (prescribed constant fluid pressures and densities) were estimated using hydraulic-head and fluid-density data obtained from about 40 wells at and near the WIPP site. The transient modeling used the calculated steady-state freshwater heads as initial conditions. 107 refs., 112 figs., 22 tabs.
LaVenue, A.M.; Haug, A.; Kelley, V.A.
Effect of oil pollution on fresh groundwater in Kuwait
Massive oil fires in Kuwait were the aftermath of the Gulf War. This resulted in the pollution of air, water, and soil, the magnitude of which is unparalleled in the history of mankind. Oil fires damaged several oil well heads, resulting in the flow of oil, forming large oil lakes. Products of combustion from oil well fires deposited over large areas. Infiltrating rainwater, leaching out contaminants from oil lakes and products of combustion at ground surface, can reach the water table and contaminate the groundwater. Field investigations, supported by laboratory studies and mathematical models, show that infiltration of oil from oil lakes will be limited to a depth of about 2 m from ground surface. Preliminary mathematical models showed that contaminated rainwater can infiltrate and reach the water table within a period of three to four days, particularly at the Raudhatain and Umm Al-Aish regions. These are the only regions in Kuwait where fresh groundwater exists. After reaching the water table, the lateral movement of contaminants is expected to be very slow under prevailing hydraulic gradients. Groundwater monitoring at the above regions during 1992 showed minor levels of vanadium, nickel, and total hydrocarbons at certain wells. Since average annual rainfall in the region is only 120 mm/yr, groundwater contamination due to the infiltration of contaminated rainwater is expected to be a long-term one. 13 refs., 15 figs., 2 tabs.
Al-Sulaimi, J.; Viswanathan, M.N.; Szekely, F. [Kuwait Institute for Scientific Research, Safat (Kuwait)
Numerical heat conduction in hydrodynamical models of colliding hypersonic flows
Hydrodynamical models of colliding hypersonic flows are presented which explore the dependence of the resulting dynamics and the characteristics of the derived X-ray emission on numerical conduction and viscosity. For the purpose of our investigation we present models of colliding flow with plane-parallel and cylindrical divergence. Numerical conduction causes erroneous heating of gas across the contact discontinuity which has implications for the rate at which the gas cools. We find that the dynamics of the shocked gas and the resulting X-ray emission are strongly dependent on the contrast in the density and temperature either side of the contact discontinuity, these effects being strongest where the postshock gas of one flow behaves quasi-adiabatically while the postshock gas of the other flow is strongly radiative. Introducing additional numerical viscosity into the simulations has the effect of damping the growth of instabilities, which in some cases act to increase the volume of shocked gas and can re-he...
Parkin, E R
GEOL4850 (GEOL5850) Groundwater Hydrology University of North Texas
or by appointment. Email: email@example.com Textbooks : Hudak P., Principles of Hydrogeology (Third Edition), CRC Press. Properties of aquifers ---porosity and specific yield, hydraulic conductivity, water table and potentiometric of groundwater flow ---hydraulic head, Darcy's law, equations of groundwater flow in confined and unconfined
Pan, Feifei
Recent Advances in Computational Techniques for Simulation of Flow in Porous Media
are also addressed. Introduction Modeling porous media flow processes is required in many science and engineering applications. Oil recovery, environmental hydrology and groundwater flow are a few drivers in the development of porous media simulation tools. Nowadays high resolution models are constructed as a result
Coutinho, Alvaro L. G. A.
The mathematical structure of multiphase thermal models of flow in porous media
The mathematical structure of multiphase thermal models of flow in porous media By Daniel E.A. van with the formulation and numerical solution of equations for modelling multicomponent, two-phase, thermal fluid flow typical flow behaviour that occurs during fluid injection into a reservoir. Keywords: porous media flow
A simple segregated flow model for a WAG process
integration, a volumetric balance of the injectants and the initial reservoir fluids is obtained. The model was developed with several simplifying assumptions including immiscible water and gas phases, incompressible fluid f'low, no trapped oil volumes... with the process are the relatively higher sweep efficiencies of water floods and the low residual oil saturations of miscible gas injection. The mechanism oP water flooding is generally well understood. Many Pields have been and still are being waterflooded...
Hopkins, Christopher Wright
The influence of naturally-occurring organic acids on model estimates of lakewater acidification using the model of acidification of groundwater in catchments (MAGIC)
A project for the US Department of Energy, entitled Incorporation of an organic acid representation into MAGIC (Model of Acidification of Groundwater in Catchments) and Testing of the Revised Model UsingIndependent Data Sources'' was initiated by E S Environmental Chemistry, Inc. in March, 1992. Major components of the project include: improving the MAGIC model by incorporating a rigorous organic acid representation, based on empirical data and geochemical considerations, and testing the revised model using data from paleolimnological hindcasts of preindustrial chemistry for 33 Adirondack Mountain lakes, and the results of whole-catchment artificial acidification projects in Maine and Norway. The ongoing research in this project involves development of an organic acid representation to be incorporated into the MAGIC modeland testing of the improved model using three independent data sources. The research during Year 1 has included conducting two workshops to agree on an approach for the organic acid modeling, developing the organic subroutine and incorporating it into MAGIC (Task 1), conducing MAGIC hindcasts for Adirondack lakes and comparing the results with paleolimnological reconstructions (Task 2), and conducting site visits to the manipulation project sites in Maine and Norway. The purpose of this report is to provide a summary of the work that has been conducted on this project during Year 1. Tasks 1 and 2 have now been completed.
Sullivan, T.J.; Eilers, J.M. (E and S Environmental Chemistry, Inc., Corvallis, OR (United States)); Cosby, B.J. (Virginia Univ., Charlottesville, VA (United States). Dept. of Environmental Sciences); Driscoll, C.T. (Syracuse Univ., NY (United States). Dept. of Civil Engineering); Hemond, H.F. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil Engineering); Charles, D.F.
FRAMES-2.0 Software System: Linking to the Groundwater Modeling System (GMS) RT3D and MT3DMS Models
Linkages to the Groundwater Modeling System have been developed at Pacific Northwest National Laboratory to enable the Nuclear Regulatory Commission (NRC) to more realistically assess the risk to the public of radioactive contaminants at NRC-licensed sites. Common software tools presently in use are limited in that they cannot assess contaminant migration through complex natural environments. The purpose of this initiative is to provide NRC with a licensing safety-analysis tool with sufficient power, flexibility, and utility that it can serve as the primary software platform for analyzing the hazards associated with licensing actions at those �complex� sites at which the traditional tools are inappropriate. As a tool designed to realistically approximate prospective doses to the public, this initiative addresses NRC�s safety-performance goal by confirming that licensing actions do not result in undue risk to the public.
Whelan, Gene; Castleton, Karl J.; Pelton, Mitch A.
Compositional modeling of threephase flow with gravity using higherorder finite element methods
Compositional modeling of threephase flow with gravity using higherorder finite element methods using higherorder finite element methods. Gravity poses complications in modeling multiphase processes flow with gravity using higherorder finite element methods, Water Resour. Res., 47, W05511, doi:10
Firoozabadi, Abbas
FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties
A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a limited techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply, and cost models for supplying seawater and saline groundwater. We estimate that combined, within the coterminous US these resources can support production on the order of 9.46E+7 m3 yr-1 (25 billion gallons yr-1) of renewable biodiesel. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Geographically, water availability is most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate and various saline waters are economically available. As a whole, barren and scrub lands of the southwestern US have limited freshwater supplies so accurate assessment of alternative waters is critical.
Venteris, Erik R.; Skaggs, Richard; Coleman, Andre M.; Wigmosta, Mark S.
Two- and Three-Dimensional Depiction of Subsurface Geology Using Commercial Software for Support of Groundwater Contaminant Fate and Transport Analysis - 13345
Groundwater contamination by hexavalent chromium and other nuclear reactor operation-related contaminants has resulted in the need for groundwater remedial actions within the Hanford Site reactor areas (the Hanford Site 100 Area). The large geographic extent of the resultant contaminant plumes requires an extensive level of understanding of the aquifer structure, characteristics, and configuration to support assessment and design of remedial alternatives within the former 100-D, 100-H, and 100-K reactor areas. The authors have prepared two- and three-dimensional depictions of the key subsurface geologic structures at two Hanford Site reactor operable units (100-K and 100-D/H). These depictions, prepared using commercial-off-the-shelf (COTS) visualization software, provide a basis for expanding the understanding of groundwater contaminant migration pathways, including identification of geologically-defined preferential groundwater flow pathways. These identified preferential flow pathways support the conceptual site model and help explain both historical and current contaminant distribution and transport. (authors)
Ivarson, Kristine A. [North Wind, Inc. Richland, Washington 99352 (United States)] [North Wind, Inc. Richland, Washington 99352 (United States); Miller, Charles W.; Arola, Craig C. [CH2M HILL Plateau Remediation Company, Richland, Washington 99352 (United States)] [CH2M HILL Plateau Remediation Company, Richland, Washington 99352 (United States)
Comparison of two conceptual models of flow using the TSA
As part of the performance-assessment task for the potential repository site at Yucca Mountain, Nevada, Sandia National Laboratories is developing a set of programs called the Total-System Analyzer (TSA). The TSA is one of the tools being used in the current effort to provide a systematic preliminary estimate the total-system performance of the Yucca Mountain site. The purposes of this paper are twofold: (1) to describe capabilities that have been added to the TSA in the last year; and (2) to present a comparison of two conceptual models of unsaturated-zone flow and transport, in terms of the performance measure specified by the Environmental Protection Agency (EPA) in 40 CFR Part 191. The conceptual-model comparison is intended to demonstrate the new TSA capabilities and at the same time shed some light on the performance implications of fracture flow at Yucca Mountain. Unsaturated fracture flow is not yet well understood, and it is of great importance in determining the performance of Yucca Mountain.
Wilson, M.L.
Hydrodynamical model for $J/?$ suppression and elliptic flow
In a hydrodynamic model, we have studied $J/\\psi$ suppression and elliptic flow in Au+Au collisions at RHIC energy $\\sqrt{s}$=200 GeV. At the initial time, $J/\\psi$'s are randomly distributed in the fluid. As the fluid evolve in time, the free streaming $J/\\psi$'s are dissolved if the local fluid temperature exceeds a melting temperature $T_{J/\\psi}$. Sequential melting of charmonium states ($\\chi_c$, $\\psi\\prime$ and $J/\\psi$), with melting temperatures $T_{\\chi_c}=T_{\\psi\\prime} \\approx 1.2T_c$, $T_{J/\\psi} \\approx2T_c$ and feed-down fraction $F\\approx 0.3$, is consistent with the PHENIX data on $J/\\psi$ suppression and near zero elliptic flow for $J/\\psi$'s. It is also shown that the model will require substantial regeneration of charmoniums, if the charmonium states dissolve at temperature close to the critical temperature, $T_{\\chi_c}=T_{\\psi\\prime} \\leq T_c$, $T_{J/\\psi}\\approx1.2T_c$. The regenerated charmoniums will have positive elliptic flow.
A. K. Chaudhuri
The inhomogeneous kinematic wave traffic flow model as a resonant nonlinear system
The inhomogeneous kinematic wave traffic flow model as a resonant nonlinear system December, 2000 W 95616 Abstract The kinematic wave traffic flow model for an inhomogeneous road is studied as a resonant conform to expectations. Introduction The kinematic wave traffic flow model of LWR was introduced
Mease, Kenneth D.
Model Free Closed-Loop Flow Control ERCAN ATAM, LIONEL MATHELIN, LAURENT CORDIER
Model Free Closed-Loop Flow Control ERCAN ATAM, LIONEL MATHELIN, LAURENT CORDIER *CNRS- Mathelin-Cordier (LIMSI-CNRS,IP') Model Free Closed-Loop Flow Control ECCOMAS'12 1 / 21 #12;Outline 1 and some future work Atam- Mathelin-Cordier (LIMSI-CNRS,IP') Model Free Closed-Loop Flow Control ECCOMAS'12
Mathelin, Lionel
Physics-Based, Reduced-Order Combustor Flow Modeling Sean D. Bradshaw
Physics-Based, Reduced-Order Combustor Flow Modeling by Sean D. Bradshaw B.S., Aeronautics-Based, Reduced-Order Combustor Flow Modeling by Sean D. Bradshaw Submitted to the Department of Aeronautics in Aeronautics And Astronautics Abstract A physics-based, reduced-order combustor flow model, CFLOW, is described
Peraire, Jaime
MODELLING OF SUPERSONIC GAS FLOW OF NOZZLES FOR LASER CUTTING SYSTEMS I. Dohnke1 , D. Peter1 , J. The supersonic gas flow of nozzles for laser cutting systems has been modelled with CFD simulations% and maintaining the cutting quality compared to our standard product. Keywords: modelling of gas flow behaviour
Accurate Subgrid Models for Two-Phase Flow in Heterogeneous Reservoirs
have a strong influence on flow and transport in oil reservoirs. In this work, a new modelAccurate Subgrid Models for Two-Phase Flow in Heterogeneous Reservoirs Yalchin R. Efendiev, SPE for the representation of subgrid terms is introduced and applied to two-phase reservoir flows. The model entails
Efendiev, Yalchin
A finite element model of the turbulent flow field in a centrifugal impeller
, or for applications such as pumps utilizing a liquid as the working medium. Full ellipticity of the flow- governing equations throughout the computational domain is rigorously retained. As a result, the model is conceptually capable of predicting real-flow effects... such as flow separation and recirculation, regardless of whether such complex flow behavior is local or massive. Applicability of the model is illustrated using a typical pump impeller of the purely centrifugal type. In presenting the computed flow field...
Hlavaty, Steven Todd
Continuous kinematic wave models of merging traffic flow
Merging junctions are important network bottlenecks, and a better understanding of merging traffic dynamics has both theoretical and practical implications. In this paper, we present continuous kinematic wave models of merging traffic flow which are consistent with discrete Cell Transmission Models with various distribution schemes. In particular, we develop a systematic approach to constructing kinematic wave solutions to the Riemann problem of merging traffic flow in supply-demand space. In the new framework, Riemann solutions on a link consist of an interior state and a stationary state, subject to admissible conditions such that there are no positive and negative kinematic waves on the upstream and downstream links respectively. In addition, various distribution schemes in Cell Transmission Models are considered entropy conditions. In the proposed analytical framework, we prove that the stationary states and boundary fluxes exist and are unique for the Riemann problem for both fair and constant distribution schemes. We also discuss two types of invariant merge models, in which local and discrete boundary fluxes are the same as global and continuous ones. With numerical examples, we demonstrate the validity of the analytical solutions of interior states, stationary states, and corresponding kinematic waves. Discussions and future studies are presented in the conclusion section.
Wen-Long Jin
Watershed response and land energy feedbacks under climate change depend upon groundwater.
Human induced climate change will have a significant impact on the hydrologic cycle, creating changes in fresh water resources, land cover, and feedbacks that are difficult to characterize, which makes it an issue of global importance. Previous studies have not included subsurface storage in climate change simulations and feedbacks. A variably-saturated groundwater flow model with integrated overland flow and land surface model processes is used to examine the interplay between coupled water and energy processes under climate change conditions. A case study from the Southern Great Plains (SGP) USA, an important agricultural region that is susceptible to drought, is used as the basis for three scenarios simulations using a modified atmospheric forcing dataset to reflect predicted effects due to human-induced climate change. These scenarios include an increase in the atmospheric temperature and variations in rainfall amount and are compared to the present-day climate case. Changes in shallow soil saturation and groundwater levels are quantified as well as the corresponding energy fluxes at the land surface. Here we show that groundwater and subsurface lateral flow processes are critical in understanding hydrologic response and energy feedbacks to climate change and that certain regions are more susceptible to changes in temperature, while others to changes in precipitation. This groundwater control is critical for understanding recharge and drought processes, possible under future climate conditions.
Maxwell, R M; Kollet, S J
Hanford Site Groundwater Monitoring for Fiscal Year 2003
This report presents the results of groundwater and vadose zone monitoring and remediation for fiscal year 2003 (October 2002 through September 2003) on the U.S. Department of Energy's Hanford Site, Washington. The most extensive contaminant plumes in groundwater are tritium, iodine-129, and nitrate, which all had multiple sources and are very mobile in groundwater. The largest portions of these plumes are migrating from the central Hanford Site to the southeast, toward the Columbia River. Concentrations of tritium, nitrate, and some other contaminants continued to exceed drinking water standards in groundwater discharging to the river in some locations. However, contaminant concentrations in river water remained low and were far below standards. Carbon tetrachloride and associated organic constituents form a relatively large plume beneath the central part of the Hanford Site. Hexavalent chromium is present in smaller plumes beneath the reactor areas along the river and beneath the central part of the site. Strontium-90 exceeds standards beneath all but one of the reactor areas, and technetium-99 and uranium are present in the 200 Areas. Uranium exceeds standards in the 300 Area in the south part of the Hanford Site. Minor contaminant plumes with concentrations greater than standards include carbon-14, cesium-137, cis-1,2-dichloroethene, cyanide, fluoride, plutonium, and trichloroethene. Monitoring for the ''Comprehensive Environmental Response, Compensation, and Liability Act'' is conducted in 11 groundwater operable units. The purpose of this monitoring is to define and track plumes and to monitor the effectiveness of interim remedial actions. Interim groundwater remediation in the 100 Areas continued with the goal of reducing the amount of chromium (100-K, 100-D, and 100-H) and strontium-90 (100-N) reaching the Columbia River. The objective of two interim remediation systems in the 200 West Area is to prevent the spread of carbon tetrachloride and technetium-99/uranium plumes. ''Resource Conservation and Recovery Act'' groundwater monitoring continued at 24 waste management areas during fiscal year 2003: 15 under interim or final status detection programs and data indicate that they are not adversely affecting groundwater; 7 under interim status groundwater quality assessment programs to assess contamination; and 2 under final status corrective-action programs. During calendar year 2003, drillers completed seven new RCRA monitoring wells, nine wells for CERCLA, and two wells for research on chromate bioremediation. Vadose zone monitoring, characterization, and remediation continued in fiscal year 2003. Remediation and associated monitoring continued at a soil-vapor extraction system in the 200 West Area, which removes gaseous carbon tetrachloride from the vadose zone. Soil vapor also was sampled to locate carbon tetrachloride sites with the potential to impact groundwater in the future. DOE uses geophysical methods to monitor potential movement of contamination beneath single-shell tank farms. During fiscal year 2003, DOE monitored selected boreholes within each of the 12 single-shell tank farms. In general, the contaminated areas appeared to be stable over time. DOE drilled new boreholes at the T Tank Farm to characterize subsurface contamination near former leak sites. The System Assessment Capability is a set of computer modules simulating movement of contaminants from waste sites through the vadose zone and groundwater. In fiscal year 2003, it was updated with the addition of an atmospheric transport module and with newer versions of models including an updated groundwater flow and transport model.
Hartman, Mary J.; Morasch, Launa F.; Webber, William D.
Mixed Waste Management Facility Groundwater Monitoring Report
During fourth quarter 1997, eleven constituents exceeded final Primary Drinking Water Standards (PDWS) in groundwater samples from downgradient monitoring wells at the Mixed Waste Management Facility. No constituents exceeded final PDWS in samples from upgradient monitoring wells. As in previous quarters, tritium and trichloroethylene were the most widespread elevated constituents. The groundwater flow directions and rates in the three hydrostratigraphic units were similar to those of previous quarters.
Chase, J.
Heat flow and geothermal studies in the Great Plains
In continental heat flow studies, sedimentary basins are usually avoided because of difficulties in obtaining thermal conductivity measurements and because temperature gradients may contain advective signals caused by moving groundwater. These problems are superimposed in the Denver, Kennedy and Williston Basins where complex geothermal gradients derive both from large contrasts among thermal conductivities of strata and from regional groundwater flow. The occurrence and magnitude of advective heat flow within the Denver, Kennedy and Williston Basins is conceptually consistent with simple models that relate groundwater flow to the piezometric surface and to subsurface structures, i.e., folds and faults. An advective heat flow of +25 mW/m/sup 2/ has been determined for an area in the eastern margin of the Denver Basin, and quantities of +35 mW/m/sup 2/ and +10 MW/m/sup 2/ have been determined respectively for parts of the southeastern and northeastern parts of the Williston Basin. A detailed analysis of bottom hole temperatures obtained from drill holes in the area of the Billings Anticline in the Williston Basin indicates that information on subsurface structures and groundwater flow may be obtained from heat flow studies. Additional information that may be derived from these heat flow studies includes: the occurrence and nature of geothermal resources, oil source rock maturation and secondary migration of petroleum, formation and deposition of strata-bound ores. 43 references.
Gosnold, W.D.; Fischer, D.W.
Application of LSQR to Calibration of a MODFLOW Model: A Synthetic Study Chris Muffels1,2
Tonkin2,3 , Haijiang Zhang1 , Mary Anderson1 , Tom Clemo4 1 University of Wisconsin-Madison, muffels, email@example.com, Boise, ID, USA ABSTRACT The inverse problem in groundwater modeling is often of the LSQR method for solving the inverse problem for groundwater flow using a synthetic model and compare
Barrash, Warren
Engineered Barrier System Degradation, Flow, and Transport Process Model Report
The Engineered Barrier System Degradation, Flow, and Transport Process Model Report (EBS PMR) is one of nine PMRs supporting the Total System Performance Assessment (TSPA) being developed by the Yucca Mountain Project for the Site Recommendation Report (SRR). The EBS PMR summarizes the development and abstraction of models for processes that govern the evolution of conditions within the emplacement drifts of a potential high-level nuclear waste repository at Yucca Mountain, Nye County, Nevada. Details of these individual models are documented in 23 supporting Analysis/Model Reports (AMRs). Nineteen of these AMRs are for process models, and the remaining 4 describe the abstraction of results for application in TSPA. The process models themselves cluster around four major topics: ''Water Distribution and Removal Model, Physical and Chemical Environment Model, Radionuclide Transport Model, and Multiscale Thermohydrologic Model''. One AMR (Engineered Barrier System-Features, Events, and Processes/Degradation Modes Analysis) summarizes the formal screening analysis used to select the Features, Events, and Processes (FEPs) included in TSPA and those excluded from further consideration. Performance of a potential Yucca Mountain high-level radioactive waste repository depends on both the natural barrier system (NBS) and the engineered barrier system (EBS) and on their interactions. Although the waste packages are generally considered as components of the EBS, the EBS as defined in the EBS PMR includes all engineered components outside the waste packages. The principal function of the EBS is to complement the geologic system in limiting the amount of water contacting nuclear waste. A number of alternatives were considered by the Project for different EBS designs that could provide better performance than the design analyzed for the Viability Assessment. The design concept selected was Enhanced Design Alternative II (EDA II).
E.L. Hardin
The impacts of climate change on the groundwater system of the upper Danube catchment derived from piezometric head and groundwater quality
. Keywords: Groundwater levels, groundwater quality, time series analysis 1. Introduction Understanding results, a concept for modeling changes in groundwater and chemistry coupled with regional climate change1 The impacts of climate change on the groundwater system of the upper Danube catchment derived
ancillary data is fundamental to the process of modelling a groundwater system. In an unconfined aquifer of the unconfined groundwater parameters as the unique minimum of a convex functional. 1. Introduction It is commonTHE RECONSTRUCTION OF GROUNDWATER PARAMETERS FROM HEAD DATA IN AN UNCONFINED AQUIFER IAN KNOWLES
Subgrid-scale model for the temperature fluctuations in reacting hypersonic turbulent flows
Subgrid-scale model for the temperature fluctuations in reacting hypersonic turbulent flows M. Pino fluctuations for use in large-eddy simulations of turbulent, reacting hypersonic flows. The proposed model uses, a greater understand- ing of turbulent hypersonic flows is needed. Direct numerical simulations DNS
Martín, Pino
A Comparison of the AC and DC Power Flow Models for LMP Calculations
A Comparison of the AC and DC Power Flow Models for LMP Calculations Thomas J. Overbye, Xu Cheng power flow model for LMP-based market calculations. The paper first provides a general discussion of balanced, three phase, electric power transmission networks is through the solution of the power flow. From
A flow resistance model for assessing the impact of vegetation on flood routing mechanics
control in urban storm water runoff [Kirby et al., 2005], and linking tidal hydrodynamic forcing to flow and field studies. The proposed model asymptotically recovers the flow resistance formulation when the waterA flow resistance model for assessing the impact of vegetation on flood routing mechanics Gabriel G
MODELING THE EFFECT OF FLOW FIELD DESIGN ON PEM FUEL CELL PERFORMANCE Jeffrey Glandt, Sirivatch University of South Carolina Columbia, SC 29208 firstname.lastname@example.com Key words: PEM fuel cell, flow field or printed in its publications. #12;2 MODELING THE EFFECT OF FLOW FIELD DESIGN ON PEM FUEL CELL PERFORMANCE
Van Zee, John W.
Analysis of models for induced gas flow in the unsaturated zone Kehua You,1
Analysis of models for induced gas flow in the unsaturated zone Kehua You,1 Hongbin Zhan,1 term are frequently employed in modeling the induced gas flow in an unsaturated zone underlying a leaky 2011. [1] Accurate description of induced gas flow in an unsaturated zone is indispensable
A discrete model for compressible flows in heterogeneous media
This work deals with the building of a discrete model able to describe and to predict the evolution of complex gas flows in heterogeneous media. In many physical applications, large scales numerical simulation is no longer possible because of a lack of computing resources. Indeed the medium topology may be complex due to the presence of many obstacles (walls, pipes, equipments, geometric singularities etc.). Aircraft powerplant compartments are examples where topology is complex due to the presence of pipes, ducts, coolers and other equipment. Other important examples are gas explosions and large scale dispersion of hazardous materials in urban places, cities or underground involving obstacles such as buildings and various infrastructures. In all cases efficient safety responses are required. Then a new discrete model is built and solved in reasonable execution times for large cells volumes including such obstacles. Quantitative comparisons between experimental and numerical results are shown for different significant test cases, showing excellent agreement.
Le Metayer, O., E-mail: email@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France); Massol, A., E-mail: email@example.com [AIRBUS Operations SAS, Coc Powerplant, EDET30, M0112/5, 316 Route de Bayonne, 31060 Toulouse Cedex 09 (France); Favrie, N., E-mail: firstname.lastname@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France); Hank, S., E-mail: email@example.com [IUSTI, UMR CNRS 6595, Universite Aix-Marseille I, Technopole de Chateau Gombert, 5 Rue E. Fermi, 13453 Marseille Cedex 13 (France); SMASH project, INRIA, 2004 route des Lucioles, 06902 Sophia Antipolis (France)
Modeling environmental effects on the size-structured energy flow through marine ecosystems. Part 1: The model
Modeling environmental effects on the size-structured energy flow through marine ecosystems. Part 1 size-structured mathematical model of the energy flow through marine ecosystems, based on established-dependent. The physiological bases of the model are derived from the dynamic energy budget theory. The model outputs
Poggiale, Jean-Christophe
Wellbore storage in geothermal wells: presented at 1979two-phase flow in a geothermal well has been modelled with asteam water flow in geothermal wells: Journal of Petroleum
Miller, Constance W.
Gyrokinetic and Gyrofluid Models for Zonal Flow Dynamics in Ion and Electron Temperature Gradient Turbulence
Collisionless time evolution of zonal flows in ion and electron temperature gradient turbulence in toroidal plasmas is investigated. The responses of the zonal-flow potential to the initial perturbation and to the turbulence source are determined from the gyrokinetic equations combined with the Poisson equation, A novel gyrofluid model is presented, which properly describes the zonal-flow time evolution and reproduces the same residual zonal-flow levels as predicted by the gyrokinetic model.
Sugama, H.; Watanabe, T.-H. [National Institute for Fusion Science, Toki, Gifu, 509-5292 (Japan); Graduate University for Advanced Studies, Toki, Gifu, 509-5292 (Japan); Ferrando i Margalet, S. [National Institute for Fusion Science, Toki, Gifu, 509-5292 (Japan)
The Hanford Story: Groundwater
This second chapter of The Hanford Story explains how more than 100 square miles of groundwater under the Hanford Site became contaminated and what workers are doing to restore groundwater to its highest beneficial use.
Groundwater Protection Act (Iowa)
The Commissioner of the Iowa Department of Natural Resources is required to determine a general groundwater protection strategy and groundwater quality standards for the state, to be approved by...
A simple model of gas flow in a porous powder compact
This report describes a simple model for ideal gas flow from a vessel through a bed of porous material into another vessel. It assumes constant temperature and uniform porosity. Transport is treated as a combination of viscous and molecular flow, with no inertial contribution (low Reynolds number). This model can be used to fit data to obtain permeability values, determine flow rates, understand the relative contributions of viscous and molecular flow, and verify volume calibrations. It draws upon the Dusty Gas Model and other detailed studies of gas flow through porous media.
Shugard, Andrew D.; Robinson, David B.
Hydrogeological restrictions to saline ground-water discharge in the Red River of the North drainage basin, North Dakota
Discharge of saline water from bedrock aquifers along the eastern margin of the Williston basin is restricted by surficial glacial till and lacustrine deposits in the Red River of the North drainage basin. Water from these aquifers reaches the surface by (1) diffusion; (2) slow, upward seepage along zones of relatively larger hydraulic conductivity in the till and lacustrine deposits; or (3) flow from artesian wells. Ground-water quality varies near the surface because of mixing of water being discharged from bedrock aquifers with shallower ground water in the surficial deposits. Ground-water quality, hydraulic-gradient, and hydraulic-conductivity data obtained from pumped-well and slug tests indicate that flow in the surficial deposits is eastward, but at slow rates because of small hydraulic conductivities. Base-flow and specific-conductance measurements of water in tributaries to the Red River of the North indicate that focused points of ground-water discharge result in substantial increases in salinity in surface water in the northern part of the basin in North Dakota. Core analyses and drillers' logs were used to generalize hydrogeologic characteristics of the deposits in the basin, and a two-dimensional ground-water-flow model was used to simulate the basin's geohydrologic processes. Model results indicate that the ground-water flow paths in the bedrock aquifers and surficial deposits converge, and that water from the bedrock aquifers contributes to the overall increase in ground-water discharge toward the east. Model results are supported by water-quality data collected along an east-west hydrogeologic section.
Strobel, M.L. (Geological Survey, Grand Forks, ND (United States) Univ. of North Dakota, Grand Forks, ND (United States))
A Conceptual model of coupled biogeochemical and hydrogeological processes affected by in situ Cr(VI) bioreduction in groundwater at Hanford 100H Site
in Groundwater at Hanford 100H Site B.Faybishenko, P.E.Long,Cr(VI) contaminated groundwater at Hanford 100H site. A slowHRC TM ), was injected in Hanford sediments to stimulate
MSET modeling of Crystal River-3 venturi flow meters.
The analysis of archived Crystal River-3 feedwater flow data reveals a slow and steady degradation of the flow meter measurements during the 1992/1993 operating cycle. MSET can reliably estimate the true flow rate and quantify the degree of departure between the indicated signal and the true flow rate with high accuracy. The MSET computed flow rate could, in principle, be used to provide an improved estimate of the reactor power and hence avoid the revenue loss associated with derating the reactor based on a faulty feedwater flow rate indication.
Bockhorst, F. K.; Gross, K. C.; Herzog, J. P.; Wegerich, S. W.
Three-dimensional conceptual model for the Hanford Site unconfined aquifer system: FY 1994 status report
This report documents work conducted during the fiscal year 1994 to development an improved three-dimensional conceptual model of ground-water flow in the unconfined aquifer system across the Hanford Site Ground-Water Surveillance Project, which is managed by Pacific Northwest Laboratory. The main objective of the ongoing effort to develop an improved conceptual model of ground-water flow is to provide the basis for improved numerical report models that will be capable of accurately predicting the movement of radioactive and chemical contaminant plumes in the aquifer beneath Hanford. More accurate ground-water flow models will also be useful in assessing the impacts of changes in facilities and operations. For example, decreasing volumes of operational waste-water discharge are resulting in a declining water table in parts of the unconfined aquifer. In addition to supporting numerical modeling, the conceptual model also provides a qualitative understanding of the movement of ground water and contaminants in the aquifer.
Thorne, P.D.; Chamness, M.A.; Vermeul, V.R.; Macdonald, Q.C.; Schubert, S.E.
F-Area Seepage Basins groundwater monitoring report
This progress report from the Savannah River Plant for first quarter 1992 includes discussion on the following topics: description of facilities; hydrostratigraphic units; monitoring well nomenclature; integrity of the monitoring well network; groundwater monitoring data; analytical results exceeding standards; tritium, nitrate, and pH time-trend data; water levels; groundwater flow rates and directions; upgradient versus downgradient results.
A reaction-based paradigm to model reactive chemical transport in groundwater with general kinetic and equilibrium reactions
This paper presents a reaction-based water quality transport model in subsurface flow systems. Transport of chemical species with a variety of chemical and physical processes is mathematically described by M partial differential equations (PDEs). Decomposition via Gauss-Jordan column reduction of the reaction network transforms M species reactive transport equations into two sets of equations: a set of thermodynamic equilibrium equations representing NE equilibrium reactions and a set of reactive transport equations of M-NE kinetic-variables involving no equilibrium reactions (a kinetic-variable is a linear combination of species). The elimination of equilibrium reactions from reactive transport equations allows robust and efficient numerical integration. The model solves the PDEs of kinetic-variables rather than individual chemical species, which reduces the number of reactive transport equations and simplifies the reaction terms in the equations. A variety of numerical methods are investigated for solving the coupled transport and reaction equations. Simulation comparisons with exact solutions were performed to verify numerical accuracy and assess the effectiveness of various numerical strategies to deal with different application circumstances. Two validation examples involving simulations of uranium transport in soil columns are presented to evaluate the ability of the model to simulate reactive transport with complex reaction networks involving both kinetic and equilibrium reactions.
Zhang, Fan [ORNL; Yeh, Gour-Tsyh [University of Central Florida, Orlando; Parker, Jack C [ORNL; Brooks, Scott C [ORNL; Pace, Molly [ORNL; Kim, Young Jin [ORNL; Jardine, Philip M [ORNL; Watson, David B [ORNL
Model of critical heat flux in subcooled flow boiling
The physical phenomenon occurring before and at the critical heat flux (CHF) for subcooled flow boiling has been investigated. The first phase of this study established the basic nature of the flow structure at CHF. A ...
Fiori, Mario P.
A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus
This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.
Raustad, Richard A. [Florida Solar Energy Center
Simple Models of Zero-Net Mass-Flux Jets for Flow Control Simulations
Simple Models of Zero-Net Mass-Flux Jets for Flow Control Simulations Reni Raju Dynaflow Inc for modeling the dynamics of zero- net mass-flux (ZNMF) actuators, the computational costs associated-flow model. 1. INTRODUCTION Zero-net mass-flux (ZNMF) actuators or "synthetic jets" have potential
Mittal, Rajat
A phenomenological model to describe turbulent friction in permeable-wall flows
A phenomenological model to describe turbulent friction in permeable-wall flows C. Manes,1 L impermeable rough boundaries. A novel phenomenological model that describes such anomalous behavior), A phenomenological model to describe tur- bulent friction in permeable-wall flows, Geophys. Res. Lett., 39, L14403
The McCormack model for gas mixtures: Plane Couette flow R. D. M. Garcia
The McCormack model for gas mixtures: Plane Couette flow R. D. M. Garcia HSH Scientific Computing flow for a binary gas mixture described by the McCormack kinetic model. The solution yields, defined for binary gas mixtures in terms of the McCormack model, for semi-infinite media14 Kramers
Siewert, Charles E.
Geochemical and Isotopic Evaluation of Groundwater Movement in Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nevada, Rev. No.: 0
This report describes the results of a comprehensive geochemical evaluation of the groundwater flow system in the Yucca Flat/Climax Mine Corrective Action Unit (CAU). The main objectives of this study are to identify probable pathways for groundwater flow within the study area and to develop constraints on groundwater transit times between selected data collection sites. This work provides an independent means of testing and verifying predictive flow models being developed for this CAU using finite element methods. The Yucca Flat/Climax Mine CAU constitutes the largest of six underground test areas on the Nevada Test Site (NTS) specified for remedial action in the ''Federal Facility Agreement and Consent Order''. A total of 747 underground nuclear detonations were conducted in this CAU. Approximately 23 percent of these detonations were conducted below or near the water table, resulting in groundwater contamination in the vicinity and possibly downgradient of these underground test locations. Therefore, a rigorous evaluation of the groundwater flow system in this CAU is necessary to assess potential long-term risks to the public water supply at downgradient locations.
Farnham, Irene
1 EXPERIMENTS AND MODELLING OF CAVITATING FLOWS IN VENTURI: ATTACHED SHEET CAVITATION S. Barre* , J and numerical studies were carried out to analyse cavitating flows and to describe the two- phase flow structures of attached sheet cavitation in Venturi geometries. New double optical probe measurements were
A Monte Carlo simulation method is employed to study groundwater flow in variably saturated fractal porous ... Richards' equation which is solved using a hybridized mixed finite element procedure. ... INTRODUCTION ... This conclusion has led to the development of stochastic models for the basic un- ... different soils.
Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations
Ad hoc continuum-atomistic thermostat for modeling heat flow in molecular dynamics simulations J 2004) An ad hoc thermostating procedure that couples a molecular dynamics (MD) simulation
Brenner, Donald W.
An Expert Elicitation Process in Support of Groundwater Model Evaluation for Frenchman Flat, Nevada National Security Site
The U.S. Department of Energy is implementing corrective actions at facilities where nuclear-related operations were conducted in Nevada. Among the most significant sites being addressed are the locations of underground nuclear tests on the Nevada National Security Site (NNSS). The process for implementing corrective actions for the Underground Test Area (UGTA) locations is defined in Appendix VI of a Federal Facility Agreement and Consent Order (1996, as amended). In broad terms, Appendix VI describes a Corrective Action Investigation followed by a Corrective Action Decision, and implementation of a Corrective Action Plan prior to closure. The Frenchman Flat Corrective Action Unit (CAU) is farthest along in the UGTA corrective action process. It includes ten underground tests within the Frenchman Flat topographic basin, in the southeastern portion of the NNSS. Data have been collected from drilling exploration, hydrologic testing, and field and laboratory studies. Modeling has been completed at a variety of scales and focusing on a variety of flow and transport aspects ranging from regional boundary conditions to process dynamics within a single nuclear cavity. The culmination of the investigations is a transport model for the Frenchman Flat CAU (Stoller Navarro Joint Venture, 2009) that has undergone rigorous peer review and been accepted by the State of Nevada, setting the stage for the Corrective Action Decision and progression from the investigation phase to the corrective action phase of the project.
Chapman Jenny,Pohlmann Karl
Modeling, Analysis and Simulation of Multiscale Preferential Flow - 8/05-8/10 - Final Report
The research agenda of this project are: (1) Modeling of preferential transport from mesoscale to macroscale; (2) Modeling of fast flow in narrow fractures in porous media; (3) Pseudo-parabolic Models of Dynamic Capillary Pressure; (4) Adaptive computational upscaling of flow with inertia from porescale to mesoscale; (5) Adaptive modeling of nonlinear coupled systems; and (6) Adaptive modeling and a-posteriori estimators for coupled systems with heterogeneous data.
Ralph Showalter; Malgorzata Peszynska
Preliminary Environmental Flow and Transport Modeling at the INEEL
The Idaho National Engineering and Environmental Laboratory (INEEL) is located in southeastern Idaho in the USA. The primary mission since the laboratory was founded in 1949 has been nuclear reactor research. Fifty-two reactors have been built and operated on the INEEL. Other principal activities at the laboratory have been reprocessing of spent nuclear fuel. Low-level radioactive waste generated on site and mixed and transuranic waste from the Rocky Flats plutonium processing facility in Colorado has been disposed on the INEEL at the Radioactive Waste Management Complex (RWMC). Waste disposal at the RWMC began in 1952 with shallow land burial in pits and trenches. The INEEL was placed on the National Priorities List (NPL) in 1989. The resulting environmental assessments of the potential negative health impacts of disposed waste at the RWMC have required the use of predictive numerical simulations. A petroleum reservoir simulator called TETRAD was modified for use in simulating environmental flow and transport. Use of this code has allowed the complex subsurface stratigraphy to be simulated, including an extensive region of unsaturated fractured basalt. Dual continual simulation approaches have been used to assess combined aqueous- and gaseous-phase transport of volatile organic compounds as well as dissolved-phase transport of radionuclides. Calibration of the simulator to available monitoring data has increased the confidence in the simulator results to the point where the model sensitivities are being used to direct additional characterization efforts. Eventually, as the model calibration improves and confidence in the model predictions increases, the simulator will be used as a decision tool for selecting remedial alternatives for the wastes buried at the RWMC. An overview of the overall program including a summary of laboratory actinide migration studies will be presented.
J. D. Navratil; J. M. McCarthy; S. O. Magnuson
Magnuson, Swen O; Mccarthy, James Michael; Navratil, James Dale
Nevada National Security Site Groundwater Program Welcomes Peer...
Office of Environmental Management (EM)
the computer modeling approach developed to better understand how historic underground nuclear testing in Yucca Flat affected the groundwater. In early April, five peer...
Estimation of Groundwater Recharge at Pahute Mesa using the Chloride Mass-Balance Method
Groundwater recharge on Pahute Mesa was estimated using the chloride mass-balance (CMB) method. This method relies on the conservative properties of chloride to trace its movement from the atmosphere as dry- and wet-deposition through the soil zone and ultimately to the saturated zone. Typically, the CMB method assumes no mixing of groundwater with different chloride concentrations; however, because groundwater is thought to flow into Pahute Mesa from valleys north of Pahute Mesa, groundwater flow rates (i.e., underflow) and chloride concentrations from Kawich Valley and Gold Flat were carefully considered. Precipitation was measured with bulk and tipping-bucket precipitation gauges installed for this study at six sites on Pahute Mesa. These data, along with historical precipitation amounts from gauges on Pahute Mesa and estimates from the PRISM model, were evaluated to estimate mean annual precipitation. Chloride deposition from the atmosphere was estimated by analyzing quarterly samples of wet- and dry-deposition for chloride in the bulk gauges and evaluating chloride wet-deposition amounts measured at other locations by the National Atmospheric Deposition Program. Mean chloride concentrations in groundwater were estimated using data from the UGTA Geochemistry Database, data from other reports, and data from samples collected from emplacement boreholes for this study. Calculations were conducted assuming both no underflow and underflow from Kawich Valley and Gold Flat. Model results estimate recharge to be 30 mm/yr with a standard deviation of 18 mm/yr on Pahute Mesa, for elevations >1800 m amsl. These estimates assume Pahute Mesa recharge mixes completely with underflow from Kawich Valley and Gold Flat. The model assumes that precipitation, chloride concentration in bulk deposition, underflow and its chloride concentration, have been constant over the length of time of recharge.
Cooper, Clay A [DRI] [DRI; Hershey, Ronald L [DRI] [DRI; Healey, John M [DRI] [DRI; Lyles, Brad F [DRI] [DRI
Hanford Site Groundwater Monitoring for Fiscal Year 1998
This report presents the results of groundwater and vadose-zone monitoring and remediation for fiscal year (FY) 1998 on the Word Site, Washington. Soil-vapor extraction in the 200-West Area removed 777 kg of carbon tetrachloride in FY 1998, for a total of 75,490 kg removed since remediation began in 1992. Spectral gamma logging and evaluation of historical gross gamma logs near tank farms and liquid-disposal sites in the 200 Areas provided information on movement of contaminants in the vadose zone. Water-level monitoring was performed to evaluate groundwater-flow directions, to track changes in water levels, and to relate such changes to evolving disposal practices. Water levels over most of the Hanford Site continued to decline between June 1997 and June 1998. The most widespread radiological contaminant plumes in groundwater were tritium and iodine-129. Concentrations of technetium-99, uranium, strontium-90, and carbon-14 also exceeded drinking water standards in smaller plumes. Plutonium and cesium-137 exceeded standards only near the 216-B-5 injection well. Derived concentration guide levels specified in U.S. Department of Energy Order 5400.5 were exceeded for tritium, uranium, strontium-90, and plutonium in small plumes or single wells. One well completed in the basalt-confined aquifer beneath the 200-East Area exceeded the drinking water standard for technetium-99. Nitrate is the most extensive chemical contaminant. Carbon tetrachloride, chloroform, chromium, cis-l, Z-dichloroethylene, fluoride, and trichloroethylene also were present in smaller areas at levels above their maximum contaminant levels. Cyanide concentrations were elevated in one area but were below the maximum contaminant level. Tetrachloroethylene exceeded its maximum contaminant level in several wells in the 300 Area for the first time since the 1980s. Metals such as aluminum, cadmium, iron, manganese, and nickel exceeded their maximum contaminant levels in filtered samples from numerous wells; they are believed to represent natural components of groundwater. Resource Conservation and Recovery Act of 1976 groundwater monitoring continued at 25 waste management areas during FY 1998: 17 under detection programs and data indicate that they are not adversely affecting groundwater, 6 under interim-status groundwater-quality-assessment programs to assess possible contamination, and 2 under final-status corrective-action programs. Groundwater remediation in the 100 Areas continued to reduce the amount of strontium-90 (100-N) and chromium (100-K, D, and H) reaching the Columbia River. Two systems in the 200-West Area operated to prevent the spread of carbon tetrachloride and technetide uranium plumes. Groundwater monitoring continued at these sites and at other sites where there is no active remediation. A three-dimensional, numerical groundwater model was applied to simulate radionuclide movement from sources in the 200 Areas following site closure in 2050. Contaminants will continue to move toward the southeast and north (through Gable Gap), but the areas with levels exceeding drinking water standards will diminish.
Hartman, M.J. [and others
This project is investigating countercurrent flow and �flooding� phenomena in light water reactor systems to improve reactor safety of current and future reactors. To better understand the occurrence of flooding in the surge line geometry of a PWR, two experimental programs were performed. In the first, a test facility with an acrylic test section provided visual data on flooding for air-water systems in large diameter tubes. This test section also allowed for development of techniques to form an annular liquid film along the inner surface of the �surge line� and other techniques which would be difficult to verify in an opaque test section. Based on experiences in the air-water testing and the improved understanding of flooding phenomena, two series of tests were conducted in a large-diameter, stainless steel test section. Air-water test results and steam-water test results were directly compared to note the effect of condensation. Results indicate that, as for smaller diameter tubes, the flooding phenomena is predominantly driven by the hydrodynamics. Tests with the test sections inclined were attempted but the annular film was easily disrupted. A theoretical model for steam venting from inclined tubes is proposed herein and validated against air-water data. Empirical correlations were proposed for air-water and steam-water data. Methods for developing analytical models of the air-water and steam-water systems are discussed, as is the applicability of the current data to the surge line conditions. This report documents the project results from July 1, 2005 through June 30, 2008.
Vierow, Karen
Development of a model to predict flow oscillations in low-flow sodium boiling
An experimental and analytical program has been carried out in order to better understand the cause and effect of flow oscillations in boiling sodium systems. These oscillations have been noted in previous experiments with ...
Levin, Alan Edward
Liquid Water Dynamics in a Model Polymer Electrolyte Fuel Cell Flow Channel
Liquid Water Dynamics in a Model Polymer Electrolyte Fuel Cell Flow Channel by Chris Miller in a Model Polymer Electrolyte Fuel Cell Flow Channel by Chris Miller Bachelors of Engineering, University in a polymer electrolyte fuel cell is a critical issue in ensuring high cell performance. The water production
Study of a low Mach nuclear core model for two-phase flows with phase
Study of a low Mach nuclear core model for two-phase flows with phase transition I: stiffened gas law Manuel Bernard , Stéphane Dellacherie , Gloria Faccanoni , Bérénice Grec§ and Yohan Penel¶ October 30, 2012 In this paper, we are interested in modelling the flow of the coolant (water) in a nuclear
Asymptotical Computations for a Model of Flow in Saturated Porous Media
a variably saturated porous medium with exponential diffusivity, such as soil, rock or concrete is given by uAsymptotical Computations for a Model of Flow in Saturated Porous Media P. Amodio a , C.J. Budd b for an implicit second order ordinary differential equation which arises in models of flow in saturated porous
Weinmüller, Ewa B.
Ecosystem effects of environmental flows: modelling and experimental floods in a dryland river
physical system using: (1) a reservoir operations model to simulate reservoir releases and reservoir water experimental floods on the differential mortality of native and exotic riparian trees, on beaver dam integrity of model applications and experimental flow releases are contributing to adaptive flow management
Mass Flow Estimation with Model Bias Correction for a Turbocharged Diesel Engine
Mass Flow Estimation with Model Bias Correction for a Turbocharged Diesel Engine Tom�s Pol�ni. Based on an augmented observable Mean Value En- gine Model (MVEM) of a turbocharged Diesel engine in the intake duct. Keywords: Diesel engine, Mass flow estimation, Bias estimation, Kalman filtering, Mean value
Johansen, Tor Arne
Numerical modeling of fluid flow and time-lapse seismics to monitor ...
May 30, 2014 ... and saturation. The model considers the geometrical features of the formations, .... mudstone layers inside the Utsira formation the complex bulk and shear ..... obtained from the flow simulator to build a 2D model of the Utsira.
Evaluation of a CFD-model for simulation of simplified flow conditioners
Perforated plate flow conditioners are used to generate a fully developed turbulent flow profile upstream of an orifice meter. It is very time-consuming to measure the effect of a flow conditioner for different upstream flow profiles. Therefore a project is initiated to evaluate the performance of a computational fluid computer code for this purpose. If the code correctly predicts the flow characteristics downstream of more complex flow conditioners. In this study a k-{var_epsilon} CFD-model was used to predict the flow downstream of obstruction plates having one large or nine small holes. Both mean velocity, turbulent kinetic energy, k, and the dissipation rate of turbulent kinetic energy, {var_epsilon}, were calculated and compared against measured data. The results indicate that it is possible to predict the mean velocity well and that the accuracy of the predicted k and {var_epsilon} depends on the complexity of the flow.
Erdal, A. [Statoil/K-LAB, Haugesund (Norway); Torbergsen, L.E.; Rimestad, S.; Krogstad, P.A. [Norwegian Inst. of Technology, Trondheim (Norway)
Equivalent hydraulic conductivity of an experimental stratigraphy: Implications for basin-scale flow
Equivalent hydraulic conductivity of an experimental stratigraphy: Implications for basin-scale groundwater flow models are the estimation of representative hydraulic conductivity for the model units. In this study, high-resolution, fully heterogeneous basin-scale hydraulic conductivity map is generated
Gable, Carl W.
Situ treatment of contaminated groundwater
DOE Patents [OSTI]
A system for treating dissolved halogenated organic compounds in groundwater that relies upon electrolytically-generated hydrogen to chemically reduce the halogenated compounds in the presence of a suitable catalyst. A direct current is placed across at least a pair, or an array, of electrodes which are housed within groundwater wells so that hydrogen is generated at the cathode and oxygen at the anode. A pump is located within the well housing in which the cathode(s) is(are) located and draws in groundwater where it is hydrogenated via electrolysis, passes through a well-bore treatment unit, and then transported to the anode well(s) for reinjection into the ground. The well-bore treatment involves a permeable cylinder located in the well bore and containing a packed bed of catalyst material that facilitates the reductive dehalogenation of the halogenated organic compounds by hydrogen into environmentally benign species such as ethane and methane. Also, electro-osmatic transport of contaminants toward the cathode also contributes to contaminant mass removal. The only above ground equipment required are the transfer pipes and a direct circuit power supply for the electrodes. The electrode wells in an array may be used in pairs or one anode well may be used with a plurality of cathode wells. The DC current flow between electrode wells may be periodically reversed which controls the formation of mineral deposits in the alkaline cathode well-bore water, as well as to help rejuvenate the catalysis.
McNab, Jr., Walt W. (Concord, CA); Ruiz, Roberto (Tracy, CA); Pico, Tristan M. (Livermore, CA)
Groundwater Management Areas (Texas)
This legislation authorizes the Texas Commission on Environmental Quality and the Texas Water Development Board to establish Groundwater Management Areas to provide for the conservation,...
Groundwater and Wells (Nebraska)
This section describes regulations relating to groundwater protection, water wells, and water withdrawals, and requires the registration of all water wells in the state.
Hydraulic Containment of TCE Contaminated Groundwater at the DOE Portsmouth Gaseous Diffusion Plant
This paper will describe the progress of a groundwater remedial action at the Portsmouth Gaseous Diffusion Plant (PORTS), a Department of Energy (DOE) facility that enriched uranium from the early 1950's until 2000. The X-749 southern boundary hydraulic containment system, combining a four-well extraction system with a previously constructed subsurface barrier wall, has been employed at PORTS. The hydraulic containment project has been implemented as part of containment and remediation of the X-749/X-120 area trichloroethylene (TCE) contaminant. The X-749/X-120 groundwater contaminant plume is located in the south central section (Quadrant I) of the PORTS facility. The plume is associated with the former X-120 Goodyear Training Facility and a landfill known as the X-749 Contaminated Materials Disposal Facility. The principal contaminants of concern are chlorinated solvents (primarily TCE) and technetium-99 (Tc-99). A subsurface barrier wall (X-749 South Barrier Wall) was completed in 1994 at the PORTS southern reservation boundary as an interim remedial measure to slow the advancement of the leading edge of the contaminated groundwater plume or to prevent the plume from migrating off DOE property. Remedial measures identified by Ohio Environmental Protection Agency (Ohio EPA) included installation of a barrier wall around the eastern and southern portions of the X-749 landfill to provide source control and installation of a phyto-remediation system to help contain groundwater flow and remove volatile organic compounds. Previous remedial measures that were implemented as elements of 'closures' on the X-749 landfill included a multimedia cap, barrier walls, and a groundwater collection system. Despite these measures, the X-749/X-120 groundwater plume has migrated beyond the southern DOE property boundary. Current TCE concentrations in off-site groundwater monitoring wells are below the preliminary remediation goal and drinking water maximum contaminant level for TCE of 5 {mu}g/kg, but continue to increase. Hydraulic containment was selected as the method for controlling the plume at the southern DOE property boundary. Recent borings and pumping tests indicate that approximately a 400-foot section of the existing subsurface barrier wall near the DOE property boundary may been improperly keyed into the Sunbury Shale bedrock which underlies the unconsolidated uppermost Gallia sand and gravel aquifer (Gallia). This gap is reported to be as much as 4 vertical feet. In addition, the X-749 groundwater plume is migrating around the western end of the X-749 South Barrier Wall. Four groundwater extraction wells were installed at the DOE property boundary to provide hydraulic control of the plume currently flowing under and around the existing subsurface barrier wall. Placement of the new extraction wells was based on groundwater modeling and data collected from pumping tests in the area. The extracted groundwater is being sent to the on-site X-622 Groundwater Treatment Facility via subsurface piping. The hydraulic containment system began operation in June 2007. The preliminary water elevations from monitoring wells in the vicinity of two of the four extraction wells demonstrate a significant decrease in groundwater potentiometric head in the southern boundary area. The current extraction rates should be adequate to contain the leading edge of the contaminant plume. Monitoring wells in the area will continue to be sampled on a quarterly basis. (authors)
Lewis, A.C.; Rieske, D.P.G.; Baird, D.R.P.E. [CDM, Piketon, OH (United States)
Phase I Flow and Transport Model Document for Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada National Security Site, Nye County, Nevada, Revision 1 with ROTC 1
The Underground Test Area (UGTA) Corrective Action Unit (CAU) 97, Yucca Flat/Climax Mine, in the northeast part of the Nevada National Security Site (NNSS) requires environmental corrective action activities to assess contamination resulting from underground nuclear testing. These activities are necessary to comply with the UGTA corrective action strategy (referred to as the UGTA strategy). The corrective action investigation phase of the UGTA strategy requires the development of groundwater flow and contaminant transport models whose purpose is to identify the lateral and vertical extent of contaminant migration over the next 1,000 years. In particular, the goal is to calculate the contaminant boundary, which is defined as a probabilistic model-forecast perimeter and a lower hydrostratigraphic unit (HSU) boundary that delineate the possible extent of radionuclide-contaminated groundwater from underground nuclear testing. Because of structural uncertainty in the contaminant boundary, a range of potential contaminant boundaries was forecast, resulting in an ensemble of contaminant boundaries. The contaminant boundary extent is determined by the volume of groundwater that has at least a 5 percent chance of exceeding the radiological standards of the Safe Drinking Water Act (SDWA) (CFR, 2012).
Andrews, Robert
Transport parameter determination and modeling of sodium and strontium plumes at the Idaho National Engineering Laboratory
finite-element method to model a case of chromium contamination with some success. Bobcrtson, '1974~ used au iterative, alternating- direction. inrplicit finite-difference scheme to solve the groundwater flow equation and a. nrodified method... the location of the INEL and generalized groundwater flow lines of the Snake River Plain aquifer [from Barraclough et al. , 1981). . 12 3. Map showing the major facilities and surface water features at the INEL [from Robertson et al. , 1974]. 4. Volcanic...
Londergan, John Thomas
Coastal Dynamics 2013 A 3-D PHASE-AVERAGED MODEL FOR SHALLOW WATER FLOW WITH WAVES IN
Coastal Dynamics 2013 1915 A 3-D PHASE-AVERAGED MODEL FOR SHALLOW WATER FLOW WITH WAVES in coastal vegetated waters with short waves. The model adopts the 3-D phase-averaged shallow water flow mesh in the vertical direction. The flow model is coupled with a spectral wave deformation model called
US Army Corps of Engineers
Modeling the influence of optic flow on grid cell firing in the absence of other cues1
Modeling the influence of optic flow on grid cell firing in the absence of other cues1 Florian affect the firing of grid cells recorded in entorhinal cortex of rats. Optic flow provides information and superimposed with noise in order to model the optic flow that would be available to the rat. This optic flow
Hasselmo, Michael
Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholms�sen; Hydraulic and thermal groundwater modelling of a geothermal energy system in the Stockholmesker.
?? Geothermal energy can be extracted from an aquifer, where the groundwater is used as heat exchange medium while heat and cold are stored in� (more)
Landstr�m, Carolin
Constitutive modelling approach for evaluating the triggering of flow slides
The paper presents a methodology to evaluate flow slide susceptibility in potentially liquefiable sandy slopes. The proposed approach accounts for both contractive and dilative volumetric behaviour during shearing using ...
Buscarnera, Giuseppe
Modeling of stagnation-line nonequilibrium flows by means of quantum based collisional models
The stagnation-line flow over re-entry bodies is analyzed by means of a quantum based collisional model which accounts for dissociation and energy transfer in N{sub 2}-N interactions. The physical model is based on a kinetic database developed at NASA Ames Research Center. The reduction of the kinetic mechanism is achieved by lumping the rovibrational energy levels of the N{sub 2} molecule in energy bins. The energy bins are treated as separate species, thus allowing for non-Boltzmann distributions of their populations. The governing equations are discretized in space by means of the Finite Volume method. A fully implicit time-integration is used to obtain steady-state solutions. The results show that the population of the energy bins strongly deviate from a Boltzmann distribution close to the shock wave and across the boundary layer. The sensitivity analysis to the number of energy bins reveals that accurate estimation of flow quantities (such as chemical composition and wall heat flux) can be obtained by using only 10 energy bins. A comparison with the predictions obtained by means of conventional multi-temperature models indicates that the former can lead to an overestimation of the wall heat flux, due to an inaccurate modeling of recombination in the boundary layer.
Munaf�, A., E-mail: firstname.lastname@example.com; Magin, T. E., E-mail: email@example.com [Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, 1640 Rhode-Saint-Gen�se (Belgium)
Groundwater Protection Plan (West Virginia)
Groundwater Protection Plans (GPPs) are required for all facilities having the potential to impact groundwater. They are �preventive maintenance� documents that cover all processes and materials at...
The Modelling of Degenerate Neck Pinch Singularities in Ricci Flow by Bryant Solitons
In earlier work, carrying out numerical simulations of the Ricci flow of families of rotationally symmetric geometries on $S3$, we have found strong support for the contention that (at least in the rotationally symmetric case) the Ricci flow for a ``critical'' initial geometry - one which is at the transition point between initial geometries (on $S^3$) whose volume-normalized Ricci flows develop a singular neck pinch, and other initial geometries whose volume normalized Ricci flows converge to a round sphere - evolves into a ``degenerate neck pinch.'' That is, we have seen in this earlier work that the Ricci flows for the critical geometries become locally cylindrical in a neighborhood of the initial pinching, and have the maximum amount of curvature at one or both of the poles. Here, we explore the behavior of these flows at the poles, and find strong support for the conjecture that the Bryant steady solitons accurately model this polar flow.
David Garfinkle; James Isenberg
A Flow Time Model for Melt-Cast Insensitive Explosive Process Guillemin Jean-Philippe*, Brunet Luc
and inserted in our flow time equations. De Larrard's model for the calculation of the maximum packing density The purpose of this article is to propose a predictive model of the flow time necessary for emptying a reactor
Source Term Modeling for Evaluating the Potential Impacts to Groundwater of Fluids Escaping from a Depleted Oil Reservoir Used for Carbon Sequestration
In recent years depleted oil reservoirs have received special interest as carbon storage reservoirs because of their potential to offset costs through collaboration with enhanced oil recovery projects. Modeling is currently being conducted to evaluate potential risks to groundwater associated with leakage of fluids from depleted oil reservoirs used for storage of CO2. Modeling results reported here focused on understanding how toxic organic compounds found in oil will distribute between the various phases within a storage reservoir after introduction of CO2, understanding the migration potential of these compounds, and assessing potential groundwater impacts should leakage occur. Two model scenarios were conducted to evaluate how organic components in oil will distribute among the phases of interest (oil, CO2, and brine). The first case consisted of 50 wt.% oil and 50 wt.% water; the second case was 90 wt.% CO2 and 10 wt.% oil. Several key organic compounds were selected for special attention in this study based upon their occurrence in oil at significant concentrations, relative toxicity, or because they can serve as surrogate compounds for other more highly toxic compounds for which required input data are not available. The organic contaminants of interest (COI) selected for this study were benzene, toluene, naphthalene, phenanthrene, and anthracene. Partitioning of organic compounds between crude oil and supercritical CO2 was modeled using the Peng-Robinson equation of state over temperature and pressure conditions that represent the entire subsurface system (from those relevant to deep geologic carbon storage environments to near surface conditions). Results indicate that for a typical set of oil reservoir conditions (75�C, and 21,520 kPa) negligible amounts of the COI dissolve into the aqueous phase. When CO2 is introduced into the reservoir such that the final composition of the reservoir is 90 wt.% CO2 and 10 wt.% oil, a significant fraction of the oil dissolves into the vapor phase. As the vapor phase moves up through the stratigraphic column, pressures and temperatures decrease, resulting in significant condensation of oil components. The heaviest organic components condense early in this process (at higher pressures and temperatures), while the lighter components tend to remain in the vapor phase until much lower pressures and temperatures are reached. Based on the model assumptions, the final concentrations of COI to reach an aquifer at 1,520 kPa and 25�C were quite significant for benzene and toluene, whereas the concentrations of polynuclear aromatic hydrocarbons that reach the aquifer were very small. This work demonstrates a methodology that can provide COI source term concentrations in CO2 leaking from a reservoir and entering an overlying aquifer for use in risk assessments.
Cantrell, Kirk J.; Brown, Christopher F.
In situ remediation of uranium contaminated groundwater
In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment - various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field preliminary results are discussed with regard to other potential contaminated groundwater treatment applications.
Dwyer, B.P.; Marozas, D.C. [Sandia National Labs., Albuquerque, NM (United States)
In an effort to develop cost-efficient techniques for remediating uranium contaminated groundwater at DOE Uranium Mill Tailing Remedial Action (UMTRA) sites nationwide, Sandia National Laboratories (SNL) deployed a pilot scale research project at an UMTRA site in Durango, CO. Implementation included design, construction, and subsequent monitoring of an in situ passive reactive barrier to remove Uranium from the tailings pile effluent. A reactive subsurface barrier is produced by emplacing a reactant material (in this experiment various forms of metallic iron) in the flow path of the contaminated groundwater. Conceptually the iron media reduces and/or adsorbs uranium in situ to acceptable regulatory levels. In addition, other metals such as Se, Mo, and As have been removed by the reductive/adsorptive process. The primary objective of the experiment was to eliminate the need for surface treatment of tailing pile effluent. Experimental design, and laboratory and field results are discussed with regard to other potential contaminated groundwater treatment applications.
Dwyer, B.P.; Marozas, D.C.
Progress in the Development of Compressible, Multiphase Flow Modeling Capability for Nuclear Reactor Flow Applications
In nuclear reactor safety and optimization there are key issues that rely on in-depth understanding of basic two-phase flow phenomena with heat and mass transfer. Within the context of multiphase flows, two bubble-dynamic phenomena � boiling (heterogeneous) and flashing or cavitation (homogeneous boiling), with bubble collapse, are technologically very important to nuclear reactor systems. The main difference between boiling and flashing is that bubble growth (and collapse) in boiling is inhibited by limitations on the heat transfer at the interface, whereas bubble growth (and collapse) in flashing is limited primarily by inertial effects in the surrounding liquid. The flashing process tends to be far more explosive (and implosive), and is more violent and damaging (at least in the near term) than the bubble dynamics of boiling. However, other problematic phenomena, such as crud deposition, appear to be intimately connecting with the boiling process. In reality, these two processes share many details.
R. A. Berry; R. Saurel; F. Petitpas; E. Daniel; O. Le Metayer; S. Gavrilyuk; N. Dovetta
A comparison of recharge rates in aquifers of the United States based on groundwater-age data
complete model-based methods. Keywords Groundwater age . Groundwater recharge/ water budget . USA Introduction Well-constrained water budgets are needed to assess groundwater availability and manage aquifersA comparison of recharge rates in aquifers of the United States based on groundwater-age data P. B
and its effect on fluid flow is numerical simulation. A 3D finite difference numerical model is developed based on Darcy-Brinkman formulation (DBF). Using the developed simulator a flow-based inversion approach is implemented to understand the connectivity...
Izgec, Omer
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial with heat transfer along the stator, which corresponds to the experiment of Djaoui et al. [2]. Our results
Modelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove
value energy conversions such as heat engine cycles or chemical process to be carried outModelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove, Canberra AUSTRALIA E-mail: email@example.com The natural convective flow inside a concentrating solar
Marly. The EOR process in the RCP section of the Weyburn Field uses CO2 and water injection to displaceUSING TIME-LAPSE SEISMIC MEASUREMENTS TO IMPROVE FLOW MODELING OF CO2 INJECTION IN THE WEYBURN, particularly CO2. Time lapse seismic monitoring has motivated changes to the reservoir description in a flow
A simplified model of thin layer static/flowing dynamics for granular materials with yield
/deposition processes when a layer of particles is flowing over a static layer or near the destabilization and arrestA simplified model of thin layer static/flowing dynamics for granular materials with yield, 75005 Paris, France, 4 ANGE team, INRIA, CETMEF, Lab. J.-L. Lions, Paris, France Abstract We introduce
Annals of Glaciology 51(54) 2010 1 Potential flow models of suspension current air pressure
Annals of Glaciology 51(54) 2010 1 Potential flow models of suspension current air pressure Barbara Physics, University of Cambridge, UK ABSTRACT. We present, analyse and discuss air pressure data from finite-volume chute flows of dry fine snow in air. These experiments have the correct similarity criteria
McElwaine, Jim
Neural Network Modeling of Abrasive Flow Machining Alice E. Smith
-line controller for abrasive flow machining of automotive engine intake manifolds. The process is only observable of critical components. It has been applied in the aerospace, automotive, electronic and die-making industries that the Ford Contour SVT intake manifold will be an #12;aluminum alloy. An optimal intake manifold would
Smith, Alice E.
ESTIMATION OF FLOW DISTRIBUTION FOR HYDROLOGICAL MODELLING Petter Pilesj
.hkbu.edu.hk Lars Harrie Department of Surveying. University of Lund. Box 118, ht 54. S 221 00 Lund, Sweden. E-mail: firstname.lastname@example.com Abstract: This paper discusses a new approach to estimate flow direction. Holmgren (1994) summarises some of the algorithms as, #12;( ) ( )= = 8 1 tan tan j x j x i
Harrie, Lars
Radiation Modeling In Fluid Flow Iain D. Boyd
· Closing remarks #12;3 Radiation In Fluid Flows · Radiation transport is an important phenomenon in many 5800 K #12;7 Fundamentals of Radiation Transport · Radiation does not require a medium !!! dI (s, ! ) ds +(p +g )I (s, ! )+ p I (s, ! ) Radiative Transfer Equation (RTE) - spectral intensity
Wang, Wei
Modeling gas flow through microchannels and nanopores Subrata Roya)
Plasma Dynamics Laboratory, Department of Mechanical Engineering Kettering University, Flint, Michigan microchannels and nanopores. Presented two-dimensional numerical results for Poiseuille flow of a simple fluid extensively used in our everyday life. Some MEMS devices have also been designed in the field of fluid applica
Roy, Subrata
Multiscale Modeling and Simulation of Fluid Flows in Inelastic Media
in porous media (e.g. soil), Elasticity equations in heterogeneous media (concrete, asphalt), etc porous media s The Fluid-Structure interaction (FSI) problem at the microscale and numerical methods with computational solutions s Numerical upscaling of flow in deformable porous media #12;- p. 3/42 Why homogenize
Popov, Peter
PAPER 2004-277 A Multiphase Flow Approach to Modelling
and multiphase flow in a four component system, namely solids, fluidized solids, oil and gas. It is known sand particles from the solid skeleton as the mechanical (inter-granular) strength of the formation replacement, and environmental issues. There have been various works described in the literature on the study
Wan, Richard G.
Development of a novel in vitro model to study the tryptic : endothelial cells, monocytes and flow
This thesis describes the development of a novel in vitro model of monocytes transmigration under flow and use in the study of early molecular events of atherogenesis. In this work, we focused on how endothelial dysfunction, ...
Turjman, Alexis S. (Alexis Salomon)
Modeling Biogeochemistry and Flow within Heterogeneous Formations in Variably-Saturated Media
to accurately model preferential flow and tracer transport. This research is crucial to agricultural systems where soil and crop management practices modify soil structure and alter macropore densities. The comparison between deterministic and stochastic...
Arora, Bhavna
Calculation of unsteady turbulent flow around obstacles using the large eddy simulation turbulence model
The premise of the work presented here is to use a common analytical tool, Computational Fluid Dynamics (CFD), along with a prevalent turbulence model, Large Eddy Simulation (LES), to study the flow past rectangular cylinders. In an attempt to use...
Helton, Donald McLean
Modeling and Detection of Content and Packet Flow Anomalies at Enterprise Network Gateway
This dissertation investigates modeling techniques and computing algorithms for detection of anomalous contents and traffic flows of ingress Internet traffic at an enterprise network gateway. Anomalous contents refer to a large volume of ingress...
Lin, Sheng-Ya
Coarse-scale Modeling of Flow in Gas-injection Processes for Enhanced Oil Recovery
Coarse-scale Modeling of Flow in Gas-injection Processes for Enhanced Oil Recovery James V. Lambers of gas-injection processes for enhanced oil recovery may exhibit geometrically complex features
Lambers, James
Green Water Flow Kinematics and Impact Pressure on a Three Dimensional Model Structure
Flow kinematics of green water due to plunging breaking waves interacting with a simplified, three-dimensional model structure was investigated in laboratory. Two breaking wave conditions were tested: one with waves impinging and breaking...
Ariyarathne, Hanchapola Appuhamilage Kusalika Suranjani
Rheo-PIV Analysis of the Yielding and Flow of Model Waxy Crude Oils
Waxes are a commonly encountered precipitate that can result in the gelation of crude oils and cessation of flow in pipelines. In this work, we develop a model wax�oil system that exhibits rheological behavior similar to ...
Dimitriou, Christopher J.
Control-volume method for numerical simulation of two-phase immiscible flow in two-and
Hydrology: Groundwater hydrology; 3210 Mathematical Geophysics: Modeling; 3230 Mathematical Geophysics. This concept, which is often referred to as the discrete-fracture model, has a significant effect. Introduction [2] There is wide interest in the numerical simulation of multiphase flow in fractured
Time integration for diffuse interface models for two-phase flow
We propose a variant of the ?-scheme for diffuse interface models for two-phase flow, together with three new linearization techniques for the surface tension. These involve either additional stabilizing force terms, or a fully implicit coupling of the Navier�Stokes and Cahn�Hilliard equation. In the common case that the equations for interface and flow are coupled explicitly, we find a time step restriction which is very different to other two-phase flow models and in particular is independent of the grid size. We also show that the proposed stabilization techniques can lift this time step restriction. Even more pronounced is the performance of the proposed fully implicit scheme which is stable for arbitrarily large time steps. We demonstrate in a Taylor-flow application that this superior coupling between flow and interface equation can decrease the computation time by several orders of magnitude.
Aland, Sebastian, E-mail: email@example.com
Sequential Thermo-Hydraulic Modeling of Variably Saturated Flow in High-Level Radioactive Waste Repository
Sequential Thermo-Hydraulic Modeling of Variably Saturated Flow in High-Level Radioactive Waste-Malabry, France Key words: waste repository, geological disposal, thermo- hydraulic modeling Introduction The most developed a sequential model to predict the coupled thermo-hydraulic processes at a cell-scale radioactive
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda
Mathematical Modeling and Simulation for Applications of Fluid Flow in Porous Media \\Lambda Richard descriptions at various length scales, modeling the effects of this heterogeneity of the porous medium a computer code has been developed which gives concrete quantitative results for the total model, this out
Persistent energy flow for a stochastic wave equation model in nonequilibrium statistical mechanics
We consider a one-dimensional partial differential equation system modeling heat flow around a ring. The system includes a Klein-Gordon wave equation for a field satisfying spatial periodic boundary conditions, as well as Ornstein-Uhlenbeck stochastic differential equations with finite rank dissipation and stochastic driving terms modeling heat baths. There is an energy flow around the ring. In the case of a linear field with different (fixed) bath temperatures, the energy flow can persist even when the interaction with the baths is turned off. A simple example is given.
Lawrence E. Thomas
Estimation of unsaturated zone traveltimes for Rainier Mesa and Shoshone Mountain, Nevada Test Site, Nevada, using a source-responsive preferential-flow model
Traveltimes for contaminant transport by water from a point in the unsaturated zone to the saturated zone are a concern at Rainier Mesa and Shoshone Mountain in the Nevada Test Site, Nevada. Where nuclear tests were conducted in the unsaturated zone, contaminants must traverse hundreds of meters of variably saturated rock before they enter the saturated zone in the carbonate rock, where the regional groundwater system has the potential to carry them substantial distances to a location of concern. The unsaturated-zone portion of the contaminant transport path may cause a significant delay, in addition to the time required to travel within the saturated zone, and thus may be important in the overall evaluation of the potential hazard from contamination. Downward contaminant transport through the unsaturated zone occurs through various processes and pathways; this can lead to a broad distribution of contaminant traveltimes, including exceedingly slow and unexpectedly fast extremes. Though the bulk of mobile contaminant arrives between the time-scale end members, the fastest contaminant transport speed, in other words the speed determined by the combination of possible processes and pathways that would bring a measureable quantity of contaminant to the aquifer in the shortest time, carries particular regulatory significance because of its relevance in formulating the most conservative hazard-prevention scenarios. Unsaturated-zone flow is usually modeled as a diffusive process responding to gravity and pressure gradients as mediated by the unsaturated hydraulic properties of the materials traversed. The mathematical formulation of the diffuse-flow concept is known as Richards' equation, which when coupled to a solute transport equation, such as the advection-dispersion equation, provides a framework to simulate contaminant migration in the unsaturated zone. In recent decades awareness has increased that much fluid flow and contaminant transport within the unsaturated zone takes place as preferential flow, faster than would be predicted by the coupled Richards' and advection-dispersion equations with hydraulic properties estimated by traditional means. At present the hydrologic community has not achieved consensus as to whether a modification of Richards' equation, or a fundamentally different formulation, would best quantify preferential flow. Where the fastest contaminant transport speed is what needs to be estimated, there is the possibility of simplification of the evaluation process. One way of doing so is by a two-step process in which the first step is to evaluate whether significant preferential flow and solute transport is possible for the media and conditions of concern. The second step is to carry out (a) a basic Richards' and advection-dispersion equation analysis if it is concluded that preferential flow is not possible or (b) an analysis that considers only the fastest possible preferential-flow processes, if preferential flow is possible. For the preferential-flow situation, a recently published model describable as a Source-Responsive Preferential-Flow (SRPF) model is an easily applied option. This report documents the application of this two-step process to flow through the thick unsaturated zones of Rainier Mesa and Shoshone Mountain in the Nevada Test Site. Application of the SRPF model involves distinguishing between continuous and intermittent water supply to preferential flow paths. At Rainier Mesa and Shoshone Mountain this issue is complicated by the fact that contaminant travel begins at a location deep in the subsurface, where there may be perched water that may or may not act like a continuous supply, depending on such features as the connectedness of fractures and the nature of impeding layers. We have treated this situation by hypothesizing both continuous and intermittent scenarios for contaminant transport to the carbonate aquifer and reporting estimation of the fastest speed for both of these end members.
Brian A. Ebel; John R. Nimmo
Monitoring and Modeling Fluid Flow in a Developing EGS Reservoir
Project objectives: Better understand and model fluid injection into a tight reservoir on the edges of a hydrothermal field. Use seismic data to constrain geomechanical/hydrologic/thermal model of reservoir.
Uncertainty quantication in environmental flow and transport models
78] V. P. Singh, Kinematic Wave Modeling in Water Resources:V. P. Singh, �Kinematic wave modeling in water resources: awater content ? and precipitation rate, whose motion can be approximated using kinematic wave
Wang, Peng
Characterization of dispersion with a stochastic capillary flow model
Chair of Advisory Committee: Dr. Donald L. Beddell The two numerical models presented in this thesis simulate one dimensional ground- water Sow and solute transport through saturated porous media. The models, em- ploying the lagrangian viewpoint... model based on a soil's unsaturated hydraulic conductivity versus water content relationship, and 3) test and validate the models by comparing predicted breakthrough curves for one dimensional Sow uoth measured breahthrough curves from several...
McMahon, William Joseph
The accuracy of numerical predictions for gas/liquid two-phase flows using Computational Multiphase Fluid Dynamics (CMFD) methods strongly depends on the formulation of models governing the interaction between the continuous liquid field and bubbles of different sizes. The purpose of this paper is to develop, test and validate a multifield model of adiabatic gas/liquid flows at intermediate gas concentrations (e.g., churn-turbulent flow regime), in which multiple-size bubbles are divided into a specified number of groups, each representing a prescribed range of sizes. The proposed modeling concept uses transport equations for the continuous liquid field and for each bubble field. The overall model has been implemented in the NPHASE-CMFD computer code. The results of NPHASE-CMFD simulations have been validated against the experimental data from the TOPFLOW test facility. Also, a parametric analysis on the effect of various modeling assumptions has been performed.
Elena A. Tselishcheva; Steven P. Antal; Michael Z. Podowski; Donna Post Guillen
Fluid Flow Model Development for Representative Geologic Media | Department
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeat PumpRecordFederal7.pdfFlash_2010_-24.pdfOverview Flow Cells for Energyof
Nevada National Security Site Groundwater Program Welcomes Peer Review Team
Recently, an independent peer review team was invited to assess the groundwater characterization program at the Nevada National Security Site (NNSS). This nationally recognized group of experts, from various external organizations, will examine the computer modeling approach developed to better understand how historic underground nuclear testing in Yucca Flat affected the groundwater.
Mechanistic model for void distribution in flashing flow
A problem of discharging of an initially subcooled liquid from a high pressure condition into a low pressure environment is quite important in several industrial systems such as nuclear reactors and chemical reactors. A new model for the flashing process is proposed here based on the wall nucleation theory, bubble growth model and drift-flux bubble transport model. In order to calculate the bubble number density, the bubble number transport equation with a distributed source from the wall nucleation sites is used. The model predictions in terms of the void fraction are compared to Moby Dick and BNL experimental data. It shows that satisfactory agreements could be obtained from the present model without any floating parameter to be adjusted with data. This result indicates that, at least for the experimental conditions considered here, the mechanistic prediction of the flashing phenomenon is possible based on the present wall nucleation based model. 43 refs., 4 figs.
- Also includes relevant well information * Developed sub-grid scale model of fracture permeability as a function of normal and shear displacements - Installed in the fully...
An Inertial Cell Model for the Drag Force in Multi-phase Flow
A new model for the drag coefficient of a sphere in a concentrated system is described. It is based upon a cell-averaged model for the Stokes regime combined with a physically motivated extrapolation to arbitrary Reynolds number. It can be used as an alternative to the isolated particle drag coefficient in Euler-Lagrange modelling of solid-liquid multi-phase flow.The corresponding drag force also provides a dynamic bed equation for use in Euler-Euler modelling.
Tupper, Gary; Mainza, Aubrey
Flow-topography interactions, particle transport and plankton dynamics at the Flower Garden Banks: a modeling study
influenced flow at the Flower Garden Banks, two small but thriving coral reef ecosystems in the northwest Gulf of Mexico. Flow past the modeled banks is characterized by vortex shedding, turbulent wake formation and strong return velocities in the near...
Francis, Simone
Low-Level Detections of Halogenated Volatile Organic Compounds in Groundwater
compounds; Groundwater management; Drinking water. Introduction Approximately one-half of the U and Hitt 2006 , or more complex process-based analyses utilizing groundwater models Eberts et al. 2005Low-Level Detections of Halogenated Volatile Organic Compounds in Groundwater: Use in Vulnerability
Role of Climate Variability in Modulating the Surface Water and Groundwater Interaction
from the ECHAM4.5 general circulation model indicate that it is possible to quantify groundwater variability; Groundwater-surface water interaction; Hydroclimatology; Forecasting. Introduction ClimateRole of Climate Variability in Modulating the Surface Water and Groundwater Interaction over
Arumugam, Sankar
Determining Spatial and Temporal Inputs of Freshwater, Including Submarine Groundwater Discharge,
of freshwater into the bay. A second model using Sr2+ /Ca2+ ratios was developed to discern fresh groundwater. Florida . Submarine groundwater discharge Introduction The timing and sources of freshwater deliveryDetermining Spatial and Temporal Inputs of Freshwater, Including Submarine Groundwater Discharge
Miami, University of
An individual-based instream flow model for coexisting populations of brown and rainbow trout
This report describes an individual-based model for sympatric populations of brown and rainbow trout in a stream habitat. Hatchery rainbow trout are included as a third species. The model provides a tool for predicting flow effects on trout populations by linking the hydraulic component of the Physical Habitat Simulation (PHABSIM) methodology and an individual-based population modeling approach. PHABSIM simulates the spatial distribution of depth and velocity at different flows. The individual-based model simulates the reproduction, foraging, consumption, energetic costs, growth, habitat utilization, movement, and mortality of individual fish, and enables population attributes to be determined from relevant attributes of individual fish. The spatially explicit nature of the model permits evaluation of behavioral responses used by fish to mitigate temporary setbacks in habitat quality. This linked mechanistic modeling approach readily lends itself to the iterative process of making predictions, testing against field data, improving the model, and making more predictions. The model has been applied to a stream segment in the Tule River, California. Physical and biological data from this site are used as input to the model. Calibrating the model to abundance data was relatively easy because values for mortality parameters were not strongly constrained by empirical data. Calibrating the model to observed growth rates and habitat use was more challenging. The primary reason for developing this model has been to provide a new and complementary tool to PHABSIM that can be used in instream-flow assessments.
Van Winkle, W.; Jager, H.I.; Holcomb, B.D.
A mathematical model for unsteady mixed flows in closed water pipes
We present the derivation of a new unidirectionnal model for unsteady mixed flows in non uniform closed domains. We introduce a local reference frame to take into account the local perturbation caused by the changes of section and slope. Then an asymptotic analysis is performed to obtain a model for the free surface flow and another for the pressurised flow. By coupling these models through the transition points by the use of a common set of variables and a suitable pressure law, we obtain a simple formulation called PFS-model close to the shallow water equations with source terms. It takes into account the changes of section and the slope variation in a continuous way through transition points.
Bourdarias, Christian; Gerbi, St�phane
A distributed converging overland flow model: 2. Effect of infiltration
area; f is dependent on the depth of flow h in the following sense: f(x, t) >0 if h(x, t) >0 f(x, t) = 0 if h(x, t) = 0 We will assume further that q(x, t) > f(x, t) O< t < T 0 < x < L(1 - r) where q is the lateral inflow per unit area..., T is the duration of q, L is the length of the converging section, r is the degree of convergence, and x and t are space and time coordinates. Then the continuity and momentum equations are Oh O(uh) uh q- -- q(x, t) -- ](x, t) q- (1) Ot Ox L -- x Q = uh = a...
Fully coupled thermal-mechanical-fluid flow model for nonliner geologic systems
A single model is presented which describes fully coupled thermal-mechanical-fluid flow behavior of highly nonlinear, dynamic or quasistatic, porous geologic systems. The mathematical formulation for the model utilizes the continuum theory of mixtures to describe the multiphase nature of the system, and incremental linear constitutive theory to describe the path dependency of nonlinear material behavior. The model, incorporated in an explicit finite difference numerical procedure, was implemented in two different computer codes. A special-purpose one-dimensional code, SNEAKY, was written for initial validation of the coupling mechanisms and testing of the coupled model logic. A general purpose commercially available code, STEALTH, developed for modeling dynamic nonlinear thermomechanical processes, was modified to include fluid flow behavior and the coupling constitutive model. The fully explicit approach in the coupled calculation facilitated the inclusion of the coupling mechanisms and complex constitutive behavior. Analytical solutions pertaining to consolidation theory for soils, thermoelasticity for solids, and hydrothermal convection theory provided verification of stress and fluid flow, stress and conductive heat transfer, and heat transfer and fluid flow couplings, respectively, in the coupled model. A limited validation of the adequacy of the coupling constitutive assumptions was also performed by comparison with the physical response from two laboratory tests. Finally, the full potential of the coupled model is illustrated for geotechnical applications in energy-resource related areas. Examples in the areas of nuclear waste isolation and cut-and-fill mining are cited.
Hart, R.D.
A Kinematic Wave Traffic Flow Model for Mixed Traffic H. M. Zhang1
A Kinematic Wave Traffic Flow Model for Mixed Traffic H. M. Zhang1 Department of Civil-mail: email@example.com ABSTRACT In this paper we extend the Lighthill-Whitham-Richards kinematic wave traffic kinematic wave model developed by Lighthill, Whitham (3) and Richards (4): t+(V())x=0, V( )Q(). (3
Comparing zonal and CFD models of air flows in large indoor spaces to experimental data
A.l Mass airflow rates obtained with SD-SDF model (in g-sLaw mod� els with Specific Driven Flows, or PL-SDF mod� els.In the PL-SDF class of models, Bouia de� veloped an
Mora, L.
Modeling complex biological flows in multi-scale systems using the APDEC framework
Modeling complex biological flows in multi-scale systems using the APDEC framework David Trebotich methods are based on higher-order finite difference methods in complex geometry with adaptivity-mail: email@example.com Abstract. We have developed advanced numerical algorithms to model biological fluids
Potential Flow Model of a Vortex Street Near a Fish-like Body
Potential Flow Model of a Vortex Street Near a Fish-like Body Joshua Brulé, University of Maryland to inviscid, irrotational solutions of Navier-Stokes · Vortex potential: "A model of the lateral line of fish for vortex sensing." Ren Z, Mohseni K. 2012 #12;Vortex near a (circular) fish · (Insert your own spherical
Anlage, Steven
Assessment of Transition Model and CFD Methodology for Wind Turbine Flows
as fossil fuels are replaced by renewable alternatives. In the U.S., the Department of Energy has publishedAssessment of Transition Model and CFD Methodology for Wind Turbine Flows Aniket C. Aranake Vinod K Navier Stokes (RANS) solver with a transition model is performed for wind turbine applications
Alonso, Juan J.
Radial flow has little effect on clusterization at intermediate energies in the framework of the Lattice Gas Model
The Lattice Gas Model was extended to incorporate the effect of radial flow. Contrary to popular belief, radial flow has little effect on the clusterization process in intermediate energy heavy-ion collisions except adding an ordered motion to the particles in the fragmentation source. We compared the results from the lattice gas model with and without radial flow to experimental data. We found that charge yields from central collisions are not significantly affected by inclusion of any reasonable radial flow.
C. B. Das; L. Shi; S. Das Gupta
Development of a cell-based stream flow routing model
al. (1994) developed a 2.00x2.50 resolution river routing model for a number of World Rivers, coupled with an atmospheric-ocean model. The GCM of NASA/Goddard Institute for Space Studies (GISS) (Hansen et al., 1983) was used to calculate the runoff... resolution of 2.00 X 2.50 using the coarse river network developed by Miller et al. (1994). Input to each of the grid cell was derived from the improved GISS GCM (Hansen et al., 1983), which improved the model prediction of discharge. Costa and Foley (1997...
Raina, Rajeev
Status of the ground water flow model for the UMTRA Project, Shiprock, New Mexico, site
A two-dimensional numerical model was constructed for the alluvial aquifer in the area of the Uranium Mill Tailings Remedial Action (UMTRA) Project Shiprock, New Mexico, site. This model was used to investigate the effects of various hydrologic parameters on the evolution of the ground water flow field. Results of the model are useful for defining uncertainties in the site conceptual model and suggesting data collection efforts to reduce these uncertainties. The computer code MODFLOW was used to simulate the two-dimensional flow of ground water in the alluvium. The escarpment was represented as a no-flow boundary. The San Juan River was represented with the MODFLOW river package. A uniform hydraulic conductivity distribution with the value estimated by the UMTRA Project Technical Assistance Contractor (TAC) and a uniform recharge distribution was used. Infiltration from the flowing artesian well was represented using the well package. The ground water flow model was calibrated to ground water levels observed in April 1993. Inspection of hydrographs shows that these levels are representative of typical conditions at the site.
1VJcDona�ld, H. (1979) Combustion r 1 iodeJ�ing in Two and1979) Practical Turbulent-Combustion Interaction Models forInternation on Combustors. Combustion The 17th Symposium
Ghoniem, A.F.
Hydrogeologic properties and ground-water chemistry of the Rattlesnake Ridge interbed at well 699-25-80 (DB-14) Hanford Site
Offsite migration studies were conducted to characterize the hydraulic properties and groundwater chemistry of confined aquifer systems within the Hanford Site. These studies support the recommendations in ERDA-1538 to provide input for hydrologic modeling of groundwater flow within the Hanford Site, to afford information concerning possible contamination of underlying confined aquifer systems and to make the results available to the public. This report presents analytical results and aquifer test procedures used in characterizing the Rattlesnake Ridge interbed at well 699-25-80. The overall close association in groundwater chemistries and presence of elevated nitrate levels suggest that the Rattlesnake Ridge interbed may be locally in communication with the overlying unconfined aquifer system. Other physical evidence which indicates a potential local communication with the unconfined aquifer system includes: favorable stratigraphic position; absence of the confining Elephant Mountain basalt in surrounding areas; and intersection of a recharge boundary during aquifer tests of well 699-25-80.
Spane, F.A. Jr.; Howland, M.D.; Strait, S.R.
Lead Groundwater Contamination of Groundwater in the Northeast ...
The detailed description of the migration of pollutants is fundamental for the groundwater monitoring and it ... historical data with a, groundwater contamination sampling for water quality analyses ... can be toxic to living organisms. Lead can�...
Analysis of Refrigerant Flow and Deformation for a Flexible Short-Tube using a Finite Element Model
reliability. Short-tubes have either a constant inner dia- meter flow channel or a tapered channel with a smallAbstract A finite element model was used to simulate single-phase flow of R-22 through flexible short-tubes. The numerical model included the fluid... in the flow area. The more flexible (5513 kPa) short-tube restricted the mass flow rate more than the most rigid (9889 kPa) short-tube used in this study. The mass flow rates estimated with the finite element model were as much as 14% higher than those from...
O'Neal, D.L.; Bassiouny, R.
Comparison of analytical models for zonal flow generation in ion-temperature-gradient mode turbulence
During the past years the understanding of the multi scale interaction problems have increased significantly. However, at present there exists a flora of different analytical models for investigating multi scale interactions and hardly any specific comparisons have been performed among these models. In this work two different models for the generation of zonal flows from ion-temperature-gradient (ITG) background turbulence are discussed and compared. The methods used are the coherent mode coupling model and the wave kinetic equation model (WKE). It is shown that the two models give qualitatively the same results even though the assumption on the spectral difference is used in the (WKE) approach.
Anderson, J.; Miki, K.; Uzawa, K.; Li, J.; Kishimoto, Y. [Dept. Fundamental Energy Science, School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto, 611-0011 (Japan)
Miamisburg Environmental Management Project Archived Soil & Groundwate...
Miamisburg Environmental Management Project Archived Soil & Groundwater Master Reports Miamisburg Environmental Management Project Archived Soil & Groundwater Master Reports...
Fernald Environmental Management Project Archived Soil & Groundwater...
Fernald Environmental Management Project Archived Soil & Groundwater Master Reports Fernald Environmental Management Project Archived Soil & Groundwater Master Reports Fernald...
Friedmann-like collapsing model of a radiating sphere with heat flow
This paper considers a spherical body consisting of a fluid with heat flow which radiates in its exterior a null fluid described by the outgoing Vaidya's metric. A Friedmann-like exact solution of the interior Einstein field equations is given. It is proved that this solution, matched with the outgoing Vaidya matric, represents a physically reasonble collapsing model which, when the heat flow is switched off, reduces to the well-known collapsing model with dust. The proposed model has the remarkable property that even if the heat flow is small, the horizon will never be formed because, before this happens, the collapsing body will be destroyed by opposite gradients of pressure. 6 references.
Kolassis, C.A.; Santos, N.O.; Tsoubelis, D.
Two-phase power-law modeling of pipe flows displaying shear-thinning phenomena
This paper describes work in modeling concentrated liquid-solids flows in pipes. COMMIX-M, a three-dimensional transient and steady-state computer program developed at Argonne National Laboratory, was used to compute velocities and concentrations. Based on the authors` previous analyses, some concentrated liquid-solids suspension flows display shear-thinning rather than Newtonian phenomena. Therefore, they developed a two-phase non-Newtonian power-law model that includes the effect of solids concentration on solids viscosity. With this new two-phase power-law solids-viscosity model, and with constitutive relationships for interfacial drag, virtual mass effect, shear lift force, and solids partial-slip boundary condition at the pipe walls, COMMIX-M is capable of analyzing concentrated three-dimensional liquid-solids flows.
Ding, Jianmin; Lyczkowski, R.W.; Sha, W.T.
consumption and increase of electricity prices in a context of worldwide competition also mo- tivate system control and energy consumption op- timization. Two different levels of complexity are pro- posed]. This short historical overview also illustrates the parallel evolution of magnetic ventilation modeling
Variable Density Flow Modeling for Simulation Framework for Regional Geologic CO{sub 2} Storage Along Arches Province of Midwestern United States
The Arches Province in the Midwestern U.S. has been identified as a major area for carbon dioxide (CO{sub 2}) storage applications because of the intersection of Mt. Simon sandstone reservoir thickness and permeability. To better understand large-scale CO{sub 2} storage infrastructure requirements in the Arches Province, variable density scoping level modeling was completed. Three main tasks were completed for the variable density modeling: Single-phase, variable density groundwater flow modeling; Scoping level multi-phase simulations; and Preliminary basin-scale multi-phase simulations. The variable density modeling task was successful in evaluating appropriate input data for the Arches Province numerical simulations. Data from the geocellular model developed earlier in the project were translated into preliminary numerical models. These models were calibrated to observed conditions in the Mt. Simon, suggesting a suitable geologic depiction of the system. The initial models were used to assess boundary conditions, calibrate to reservoir conditions, examine grid dimensions, evaluate upscaling items, and develop regional storage field scenarios. The task also provided practical information on items related to CO{sub 2} storage applications in the Arches Province such as pressure buildup estimates, well spacing limitations, and injection field arrangements. The Arches Simulation project is a three-year effort and part of the United States Department of Energy (U.S. DOE)/National Energy Technology Laboratory (NETL) program on innovative and advanced technologies and protocols for monitoring/verification/accounting (MVA), simulation, and risk assessment of CO{sub 2} sequestration in geologic formations. The overall objective of the project is to develop a simulation framework for regional geologic CO{sub 2} storage infrastructure along the Arches Province of the Midwestern U.S.
Joel Sminchak
Georgia Groundwater Use Act (Georgia)
The purpose of the Georgia Groundwater Use Act is to establish procedures to be followed to obtain a permit to withdraw, obtain or utilize groundwater and for the submission of information...
Physical Model Development and Benchmarking for MHD Flows in Blanket Design
An advanced simulation environment to model incompressible MHD flows relevant to blanket conditions in fusion reactors has been developed at HyPerComp in research collaboration with TEXCEL. The goals of this phase-II project are two-fold: The first is the incorporation of crucial physical phenomena such as induced magnetic field modeling, and extending the capabilities beyond fluid flow prediction to model heat transfer with natural convection and mass transfer including tritium transport and permeation. The second is the design of a sequence of benchmark tests to establish code competence for several classes of physical phenomena in isolation as well as in select (termed here as �canonical�,) combinations. No previous attempts to develop such a comprehensive MHD modeling capability exist in the literature, and this study represents essentially uncharted territory. During the course of this Phase-II project, a significant breakthrough was achieved in modeling liquid metal flows at high Hartmann numbers. We developed a unique mathematical technique to accurately compute the fluid flow in complex geometries at extremely high Hartmann numbers (10,000 and greater), thus extending the state of the art of liquid metal MHD modeling relevant to fusion reactors at the present time. These developments have been published in noted international journals. A sequence of theoretical and experimental results was used to verify and validate the results obtained. The code was applied to a complete DCLL module simulation study with promising results.
Ramakanth Munipalli; P.-Y.Huang; C.Chandler; C.Rowell; M.-J.Ni; N.Morley; S.Smolentsev; M.Abdou
Analytical solution for two-phase flow in a wellbore using the drift-flux model
This paper presents analytical solutions for steady-state, compressible two-phase flow through a wellbore under isothermal conditions using the drift flux conceptual model. Although only applicable to highly idealized systems, the analytical solutions are useful for verifying numerical simulation capabilities that can handle much more complicated systems, and can be used in their own right for gaining insight about two-phase flow processes in wells. The analytical solutions are obtained by solving the mixture momentum equation of steady-state, two-phase flow with an assumption that the two phases are immiscible. These analytical solutions describe the steady-state behavior of two-phase flow in the wellbore, including profiles of phase saturation, phase velocities, and pressure gradients, as affected by the total mass flow rate, phase mass fraction, and drift velocity (i.e., the slip between two phases). Close matching between the analytical solutions and numerical solutions for a hypothetical CO{sub 2} leakage problem as well as to field data from a CO{sub 2} production well indicates that the analytical solution is capable of capturing the major features of steady-state two-phase flow through an open wellbore, and that the related assumptions and simplifications are justified for many actual systems. In addition, we demonstrate the utility of the analytical solution to evaluate how the bottomhole pressure in a well in which CO{sub 2} is leaking upward responds to the mass flow rate of CO{sub 2}-water mixture.
Pan, L.; Webb, S.W.; Oldenburg, C.M.
CURRENT - A Computer Code for Modeling Two-Dimensional, Chemically Reaccting, Low Mach Number Flows
This report documents CURRENT, a computer code for modeling two- dimensional, chemically reacting, low Mach number flows including the effects of surface chemistry. CURRENT is a finite volume code based on the SIMPLER algorithm. Additional convergence acceleration for low Peclet number flows is provided using improved boundary condition coupling and preconditioned gradient methods. Gas-phase and surface chemistry is modeled using the CHEMKIN software libraries. The CURRENT user-interface has been designed to be compatible with the Sandia-developed mesh generator and post processor ANTIPASTO and the post processor TECPLOT. This report describes the theory behind the code and also serves as a user`s manual.
Winters, W.S.; Evans, G.H.; Moen, C.D.
The flow of rivers into lakes: Experiments and models
with gravity currents . . . . . 72 3.6 Generalised basins with power law shapes . . . . . . . . . . . . . 74 3.7 Comparison of different basin mixing models . . . . . . . . . . . . 75 4 Laboratory Apparatus and Techniques 77 4.1 Design of apparatus... gravity currents, E varies as a function of the bulk Richardson number, Ri, the dimensionless ratio of the stabilising gravitational potential energy of the current to the destabilising kinetic energy. Different forms of the function E(Ri) have been...
Hogg, Charles
The influence of naturally-occurring organic acids on model estimates of lakewater acidification using the model of acidification of groundwater in catchments (MAGIC). Summary of research conducted during year 1
A project for the US Department of Energy, entitled ``Incorporation of an organic acid representation into MAGIC (Model of Acidification of Groundwater in Catchments) and Testing of the Revised Model UsingIndependent Data Sources`` was initiated by E&S Environmental Chemistry, Inc. in March, 1992. Major components of the project include: improving the MAGIC model by incorporating a rigorous organic acid representation, based on empirical data and geochemical considerations, and testing the revised model using data from paleolimnological hindcasts of preindustrial chemistry for 33 Adirondack Mountain lakes, and the results of whole-catchment artificial acidification projects in Maine and Norway. The ongoing research in this project involves development of an organic acid representation to be incorporated into the MAGIC modeland testing of the improved model using three independent data sources. The research during Year 1 has included conducting two workshops to agree on an approach for the organic acid modeling, developing the organic subroutine and incorporating it into MAGIC (Task 1), conducing MAGIC hindcasts for Adirondack lakes and comparing the results with paleolimnological reconstructions (Task 2), and conducting site visits to the manipulation project sites in Maine and Norway. The purpose of this report is to provide a summary of the work that has been conducted on this project during Year 1. Tasks 1 and 2 have now been completed.
Sullivan, T.J.; Eilers, J.M. [E and S Environmental Chemistry, Inc., Corvallis, OR (United States)] [E and S Environmental Chemistry, Inc., Corvallis, OR (United States); Cosby, B.J. [Virginia Univ., Charlottesville, VA (United States). Dept. of Environmental Sciences] [Virginia Univ., Charlottesville, VA (United States). Dept. of Environmental Sciences; Driscoll, C.T. [Syracuse Univ., NY (United States). Dept. of Civil Engineering] [Syracuse Univ., NY (United States). Dept. of Civil Engineering; Hemond, H.F. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil Engineering] [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Civil Engineering; Charles, D.F. [Academy of Natural Sciences of Philadelphia, PA (United States). Patrick Center for Environmental Research] [Academy of Natural Sciences of Philadelphia, PA (United States). Patrick Center for Environmental Research; Norton, S.A. [Maine Univ., Orono, ME (United States). Dept. of Geological Sciences] [Maine Univ., Orono, ME (United States). Dept. of Geological Sciences
Assessment of One- and Two-Equation Turbulence Models for Hypersonic Transitional Flows
Many Navier-Stokes codes require that the governing equations be written in conservation form with a source term. The Spalart-Allmaras one-equation model was originally developed in substantial derivative form and when rewritten in conservation form, a density gradient term appears in the source term. This density gradient term causes numerical problems and has a small influence on the numerical predictions. Further work has been performed to understand and to justify the neglect of this term. The transition trip term has been included in the one-equation eddy viscosity model of Spalart-Allmaras. Several problems with this model have been discovered when applied to high-speed flows. For the Mach 8 flat plate boundary layer flow with the standard transition method, the Baldwin-Barth and both k-{omega} models gave transition at the specified location. The Spalart-Allmaras and low Reynolds number k-{var_epsilon} models required an increase in the freestream turbulence levels in order to give transition at the desired location. All models predicted the correct skin friction levels in both the laminar and turbulent flow regions. For Mach 8 flat plate case, the transition location could not be controlled with the trip terms as given in the Spalart-Allmaras model. Several other approaches have been investigated to allow the specification of the transition location. The approach that appears most appropriate is to vary the coefficient that multiplies the turbulent production term in the governing partial differential equation for the eddy viscosity (Method 2). When this coefficient is zero, the flow remains laminar. The coefficient is increased to its normal value over a specified distance to crudely model the transition region and obtain fully turbulent flow. While this approach provides a reasonable interim solution, a separate effort should be initiated to address the proper transition procedure associated with the turbulent production term. Also, the transition process might be better modeled with the Spalart-Allmaras turbulence model with modification of the damping function f{sub v1}. The damping function could be set to zero in the laminar flow region and then turned on through the transition flow region.
A two-phase flow model of sediment transport: transition from bedload to suspended load
The transport of dense particles by a turbulent flow depends on two dimensionless numbers. Depending on the ratio of the shear velocity of the flow to the settling velocity of the particles (or the Rouse number), sediment transport takes place in a thin layer localized at the surface of the sediment bed (bedload) or over the whole water depth (suspended load). Moreover, depending on the sedimentation Reynolds number, the bedload layer is embedded in the viscous sublayer or is larger. We propose here a two-phase flow model able to describe both viscous and turbulent shear flows. Particle migration is described as resulting from normal stresses, but is limited by turbulent mixing and shear-induced diffusion of particles. Using this framework, we theoretically investigate the transition between bedload and suspended load.
Filippo Chiodi; Philippe Claudin; Bruno Andreotti
F-Area Seepage Basins groundwater monitoring report. First quarter 1992
Passive sampling for the monitoring of organic pollutants (PAHs, BTEX) in groundwater. Application to a former
Passive sampling for the monitoring of organic pollutants (PAHs, BTEX) in groundwater. Application techniques for groundwater sampling can affect the measurement of chemical composition of water. Sampling devices such as low-flow peristaltic pumps can sample water slowly from wells to obtain representative
A Preliminary Study to Assess Model Uncertainties in Fluid Flows
of the fluid. ? The sound speed, c, is assumed to be constant even if it usually depends on the temperature and the pressure. This is a good approximation for liquids but not for gases. The sound speed is reactor-dependent. ? The Equation Of State (EOS... to the temperature. This parameter is assumed constant in this model. 7 ? ???P is the dilatation of the density due to the pressure. This parameter is also assumed constant but is different for different sound speeds. Its expression is as follows: ?? ?P = 1...
Delchini, Marc Olivier
Elliptic flow from pQCD + saturation + hydro model
We have previously predicted multiplicities and transverse momentum spectra of hadrons for the most central LHC Pb+Pb collisions at $\\sqrt{s_{NN}}=5.5$ TeV using initial state for hydrodynamic evolution from pQCD + final state saturation model. By considering binary collision and wounded nucleon profiles we extend these studies to non-central collisions, and predict the $p_{T}$ dependence of minimum bias $v_{2}$ for pions at the LHC. For protons we also show how the $p_{T}$ dependence of $v_2$ changes from RHIC to the LHC.
K. J. Eskola; H. Niemi; P. V. Ruuskanen
Transient groundwater dynamics in a coastal aquifer: The effects of tides, the lunar cycle, and the beach profile
Detailed field measurements are combined with a numerical modeling to characterize the groundwater dynamics beneath the discharge zone at Waquoit Bay, Massachusetts. Groundwater salinity values revealed a saline circulation ...
Abarca, Elena
A comparison of groundwater recharge estimation methods in the Williston and Powder River structural basins in the Northern Great Plains
A comparison of groundwater recharge estimation methods in the Williston and Powder River-water-balance (SWB) model to estimate groundwater recharge in the Williston and Powder River structural basins
1 INTRODUCTION Groundwater with a high F concentration is encountered in many places around the world and
1 INTRODUCTION Groundwater with a high F concentration is encountered in many places around composition of groundwater under paddy fields in the Maheshwaram watershed and supported by chemical modeling watershed, where groundwater is intensively abstracted for paddy irrigation. A reactive1-D geochemical model
TRANSVIP: a solute transport model based on the spatial variability of intrinsic permeability
groundwater flow and solute transport in three dimensions in both saturated and unsaturated porous media. The model simulates mechanical dispersion using a spatially vari- able intrinsic permeability field. This approach provides a, more realistic physical.... TRANSVIP is a three-dimensional flow and transport model capable of simulating contaminant transport in both saturated and unsaturated porous me- dia and does not assume Fickian dispersion. In TRANSVIP, the flow deviations that cause mechanical...
Freeze, Geoffrey Allan
Start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model
Unidirectional start-up flow of a viscoelastic fluid in a pipe with fractional Maxwell's model is studied. The flow starting from rest is driven by a constant pressure gradient in an infinite long straight pipe. By employing the method of variable separations and Heaviside operational calculus, we obtain the exact solution, from which the flow characteristics are investigated. It is found that the start-up motion of fractional Maxwell's fluid with parameters $\\alpha$ and $\\beta$, tends to be at rest as time goes to infinity, except the case of $\\beta=1$. This observation, which also can be predicted from the mechanics analogue of fractional Maxwell's model, agrees with the classical work of Friedrich and it indicates fractional Maxwell's fluid presents solid-like behavior if $\\be\
Di Yang; Ke-Qin Zhu
A Lattice Boltzmann Fictitious Domain Method for Modeling Red Blood Cell Deformation and Multiple-Cell Hydrodynamic Interactions in Flow
To model red blood cell (RBC) deformation in flow, the recently developed LBM-DLM/FD method ([Shi and Lim, 2007)29], derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain methodthe fictitious domain method, is extended to employ the mesoscopic network model for simulations of red blood cell deformation. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling red blood cell deformation and the fluid-RBC interaction is enforced by the Lagrange multiplier. To validate parameters of the RBC network model, sThe stretching numerical tests on both coarse and fine meshes are performed and compared with the corresponding experimental data to validate the parameters of the RBC network model. In addition, RBC deformation in pipe flow and in shear flow is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows.
Shi, Xing; Lin, Guang; Zou, Jianfeng; Fedosov, Dmitry A.
WAVE SPEEDS FOR AN ELASTOPLASTIC MODEL FOR TWO�DIMENSIONAL DEFORMATIONS WITH A NON�ASSOCIATIVE FLOW of variables, the character� istic speeds of plane wave solutions of the system are computed. For both plastic and elastic deformations, there are two nonzero wave speeds, referred to as fast and slow waves. It is shown
Self-sustaining turbulence in a restricted nonlinear model of plane Couette flow
This paper demonstrates the maintenance of self-sustaining turbulence in a restricted nonlinear (RNL) model of plane Couette flow. The RNL system is derived directly from the Navier-Stokes equations and permits higher resolution studies of the dynamical system associated with the stochastic structural stability theory (S3T) model, which is a second order approximation of the statistical state dynamics of the flow. The RNL model shares the dynamical restrictions of the S3T model but can be easily implemented by reducing a DNS code so that it retains only the RNL dynamics. Comparisons of turbulence arising from DNS and RNL simulations demonstrate that the RNL system supports self-sustaining turbulence with a mean flow as well as structural and dynamical features that are consistent with DNS. These results demonstrate that the simplified RNL system captures fundamental aspects of fully developed turbulence in wall-bounded shear flows and motivate use of the RNL/S3T framework for further study of wall-turbulence.
Thomas, Vaughan L.; Gayme, Dennice F. [Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, 21218 (United States); Lieu, Binh K.; Jovanovi?, Mihailo R. [Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota, 55455 (United States); Farrell, Brian F. [School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts, 02138 (United States); Ioannou, Petros J. [Department of Physics, National and Kapodistrian University of Athens, Panepistimiopolis, Zografos, Athens, 15784 (Greece)
Brinkmann Model and Double Penalization Method for the Flow Around a Porous Thin
the flow of a viscous fluid around a thin layer of porous material. Using a BKW method, we perform Keywords: Navier-Stokes equations, BKW method, penalization, porous ma- terial, thin layer. 1 Introduction are obtained with a BKW method. With these two asymptotic expansions, we will compare both models. We
Statistical Analysis of Microgravity Two-Phase Slug Flow via the Drift Flux Model
. The result was a statistically consistent microgravity slug flow data base consisting of 220 data points from 8 different experiments and the associated values for the concentration parameter, Co, and drift velocity, u_(gj). A key component for this model...
Larsen, Benjamin A
MERLOT: a model for flow and heat transfer through porous media for high heat flux applications
MERLOT: a model for flow and heat transfer through porous media for high heat flux applications A Abstract Fusion power plant studies have found helium to be an attractive coolant based on its safety tend to provide modest heat transfer performance due to their inherently low heat capacity and heat
Raffray, A. René
Modeling hydrogen and helium entrapment in flowing liquid metal surfaces as plasma-facing components in
Modeling hydrogen and helium entrapment in flowing liquid metal surfaces as plasma the PFC surface (helium and hydrogen isotopes) while accommodating high heat loads. To study this problem rather than requiring a standard vacuum system. Hydrogen isotope (DT) particles that strike the surface
Harilal, S. S.
Relative permeability for two-phase flow through corrugated tubes as model porous media
-scale simulation, moving contact line, Cahn-Hilliard model, lubrication effect Corresponding author Email address of the solid wall, pore geometry, and the initial configuration. The effects of these factors are explored, for example. Finally, transient flows, such as occur in water- oil displacement, produce temporal and spatial
Feng, James J.
Transient fluid and heat flow modeling in coupled wellbore/reservoir systems
....................................................... 66 5.3.1 Modeling Field Data ..................................................................... 68 5.3.2 Optimal Location of Permanent Downhole Gauge....................... 71 5.4 Effect of Gauge Location on Pressure-Transient Analysis... at the midpoint of the flow string................................. 70 Figure 5.26 Downhole gauge placement configurations .............................................. 71 Figure 5.27 Temperature and density profiles in the wellbore...
Izgec, Bulent
Improving Managed Environmental Water Use: Shasta River Flow and Temperature Modeling
i Improving Managed Environmental Water Use: Shasta River Flow and Temperature Modeling By SARAH and perhaps reduce some water management conflicts. Additional research for managing environmental water use manage water supplies and demands to increase water use efficiency through conservation, water markets
Lund, Jay R.
Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S in a rotor-stator cavity subjected to a superimposed throughflow with heat transfer. Nu- merical predictions field from the heat transfer process. The turbulent flux is approximated by a gradient hypothesis
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow
Computational Fluid Dynamics Modeling of a Lithium/Thionyl Chloride Battery with Electrolyte Flow W.B. Gu and C.Y. Wang GATE Center of Excellence for Advanced Energy Storage Department of Mechanical are performed using a finite volume method of computational fluid dynamics. The predicted discharge curves
Wang, Chao-Yang
A New Model of Centrality Measure based on Bidirectional Power Flow for
power flow based model to evaluate the criticality in smart grid environment. Change in direction of smart grid includes various generation options, primarily in the distribution side near consumers. Engagement of customers with the energy management systems is the most lucrative part of smart grid from
Pota, Himanshu Roy
A Novel Hyperbolization Procedure for The Two-Phase Six-Equation Flow Model
We introduce a novel approach for the hyperbolization of the well-known two-phase six equation flow model. The six-equation model has been frequently used in many two-phase flow applications such as bubbly fluid flows in nuclear reactors. One major drawback of this model is that it can be arbitrarily non-hyperbolic resulting in difficulties such as numerical instability issues. Non-hyperbolic behavior can be associated with complex eigenvalues that correspond to characteristic matrix of the system. Complex eigenvalues are often due to certain flow parameter choices such as the definition of inter-facial pressure terms. In our method, we prevent the characteristic matrix receiving complex eigenvalues by fine tuning the inter-facial pressure terms with an iterative procedure. In this way, the characteristic matrix possesses all real eigenvalues meaning that the characteristic wave speeds are all real therefore the overall two-phase flowmodel becomes hyperbolic. The main advantage of this is that one can apply less diffusive highly accurate high resolution numerical schemes that often rely on explicit calculations of real eigenvalues. We note that existing non-hyperbolic models are discretized mainly based on low order highly dissipative numerical techniques in order to avoid stability issues.
Samet Y. Kadioglu; Robert Nourgaliev; Nam Dinh
Telescopic Time-Scale Bridging for Modeling Dispersion in Rapidly Oscillating Flows
Telescopic Time-Scale Bridging for Modeling Dispersion in Rapidly Oscillating Flows Ram K between the oscillation and dispersion time scales. Here, we present a methodology based on an implicit introduced errors. The error was found to decrease with mesh refinement, but a small inherent error
Zakhor, Avideh
Application of the ``Ke'' model to open channel flows in a magnetic field
,* , Mohamed Abdou a , Neil Morley a , Alice Ying a , Tomoaki Kunugi b a Mechanical and Aerospace Engineering-133 Engineering IV, Los Angeles, CA 90095-1597, USA b Department of Nuclear Engineering, Kyoto University, Japan-conductivity fluids such as molten salts. In the present study, the ``Ke'' model equations for turbulent flows
Abdou, Mohamed
Modeling the Performance, Emissions, and Cost of an Entrained-Flow Gasification Combined Cycle System Using
1 Modeling the Performance, Emissions, and Cost of an Entrained-Flow Gasification Combined Cycle Carolina State University ABSTRACT Gasification is a globally emerging technology in commercial markets for the conversion of a variety of feedstocks, including coal, heavy residue oil, biomass, solid waste, and others
Frey, H. Christopher
A non-continuum approach to obtain a macroscopic model for the flow of traffic
by continuum models for the flow of traffic. The number of vehicles in a typical section of a freeway does not justify traffic being treated as a continuum. It is also important to recognize that the basic premises of kinetic theory are not appropriate...
Tyagi, Vipin
A PARALLEL ADAPTIVE 3D MHD SCHEME FOR MODELING CORONAL AND SOLAR WIND PLASMA FLOWS C. P. T. GROTH, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 481092143, USA K. G. POWELL Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI 481092118, USA Abstract. A parallel adaptive
De Zeeuw, Darren L.
Modeling and Feedback Control for Air Flow Regulation in Deep Pits
1 Modeling and Feedback Control for Air Flow Regulation in Deep Pits Emmanuel WITRANT and Nicolas the air). It is clear that investigating automatic control solutions and minimizing the amount of pumped to the ground turbine control and distributed sensors within the shaft; 2. air quality regulation
CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke
M2 CIRQ: Qualitative fluid flow modelling for aerospace FMEA applications Neal Snooke Department- oped on top of the MCIRQ simulator with the aim to produce an automated FMEA for aircraft fuel systems similar to pre- viously developed automated electrical FMEA. Introduction This paper describes a circuit
Snooke, Neal
Detailed numerical modeling of chemical and thermal nonequilibrium in hypersonic flows
Interest in hypersonic flows has created a large demand for physicochemical models for air flow computations around reentry bodies. Detailed physicochemical models for air in chemical and thermal nonequilibrium are needed for a realistic prediction of hypersonic flowfields. In this paper we develop a model, based on elementary physicochemical processes, for a detailed description of chemical nonequilibrium together with the excitation of internal DOFs. This model is implemented in a 2D Navier-Stokes code in order to show the strong influence of thermal nonequilibrium on the flowfields. The algorithm presented here is based on a fully conservative discretization of the inviscid fluxes in the conservation equations and uses the chain rule conservation law form for the viscous fluxes. The large system of ordinary differential and algebraic equations resulting from the spatial discretization is solved by a time-accurate semiimplicit extrapolation method. 34 refs.
Riedel, U.; Maas, U.; Warnatz, J. (Stuttgart Univ. (Germany))
An elastic-perfectly plastic flow model for finite element analysis of perforated materials
This paper describes the formulation of an elastic-perfectly plastic flow theory applicable to equivalent solid [EQS] modeling of perforated materials. An equilateral triangular array of circular penetrations is considered. The usual assumptions regarding geometry and loading conditions applicable to the development of elastic constants for EQS modeling of perforated plates are considered to apply here. An elastic-perfectly plastic [EPP] EQS model is developed for a collapse surface that includes fourth-order stress terms. The fourth order yield function has been shown to be appropriate for plates with a triangular array of circular holes. A complete flow model is formulated using the consistent tangent modulus approach based on the fourth order yield function.
Jones, D.P.; Gordon, J.L.; Hutula, D.N.; Banas, D.; Newman, J.B.
Buda-Lund hydro model and the elliptic flow at RHIC
The ellipsoidally symmetric Buda-Lund hydrodynamic model describes naturally the transverse momentum and the pseudorapidity dependence of the elliptic flow in Au+Au collisions at $\\sqrt{s_{NN}} = 130$ and 200 GeV. The result confirms the indication of quark deconfinement in Au+Au collisions at RHIC, obtained from Buda-Lund hydro model fits to combined spectra and HBT radii of BRAHMS, PHOBOS, PHENIX and STAR.
M. Csanad; T. Csorgo; B. Lorstad
Modeling of material and energy flow in an EBCHR casting system
A numerical and experimental analysis is made of fluid flow and heat transfer in a continuous casting system with an electron-beam energy source. For a cylindrical ingot confined in a water-cooled crucible, a two-dimensional, steady-state model is developed which includes the effects of free convection in the pool and conduction in the two-phase and solid regions. A modified Galerkin finite element method is used to solve for the flow and temperature fields simultaneously with the upper and lower boundaries of the pool. The calculation grid deforms along vertical spines as these phase boundaries move. Heat flows are measured in a steady-state experiment involving a short ingot and no pouring. Heat transfer coefficients representing contact resistance are determined, and measured heat flows are compared with model values. Flow and temperature fields along with solidification-zone boundaries are calculated for the experimental case and a case in which the ingot cooling is improved.
Westerberg, K.W. [Aspen Technology, Inc., Cambridge, MA (United States); McClelland, M.A. [Lawrence Livermore National Lab., CA (United States)
Modeling of material and energy flow in an EBCHR casting system