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Problem Statement: How do I change the interconversion method used by Hysys for D86/TBP and D2887/TBP? | Solution: Go to Simulation/Oil Output Settings and change the interconversion method in the drop down boxes.
You can also go to the Basis Environment, Oil Manager, Oil Input Preferences/Assay Options and change the interconversion method there.
Keywords: interconversion, D86, D2887, TBP
References: None |
Problem Statement: In some situations, we need to fix the volume flowrate of a process stream in our model. How should we do it in Aspen HYSYS? | Solution: This requirement often means one of the two things,
1. If the process stream has lower volume flow, a make-up stream need to be mixed with the process stream, or
2. If the process stream has higher volume flow, a purge stream need to be used to take away materials from the process stream.
The objective is to present a flowsheet capable of handling either case and the flowrates of makeup and purge stream need to be determined based on that of the process stream.
In the attached example, the process stream is mixed with a makeup stream. The volumetric flowrate at the outlet of the mixer will be equal to or higher than the user specified value. This stream goes into a divider. One of the outlets of the divider will take the user specified volume flowrate, and the other will purge the extra materials.
The accurate flowrates for makeup stream and purge stream is calculated in an Aspen HYSYS spreadsheet unit. On the spreadsheet named Flow Settings, there are four cells of Liq Vol Flow @ Std Cond type. The values in these cells are user specified volume flow (D1), volume flow of Process Stream (B1), volume flow of Makeup Stream (B3), and volume flow of Const Liq Vol Flow at Std Cond stream (D3). Value B1 is imported, and value B3 and D3 are calculated and exported.
The following relations hold,
1) D3 = D1
2) B3 = B1 - D1 + small amount, if B1 <= D1; B3 = 0, if B1 > D1.
When the flowrate on the Makeup Stream is higher than zero, a small amount is added to account for possible mixing effect, and to make sure that the volume flow on the stream Higher Volume Flow is actually equal or higher than the user specified value of volume flow.
The attached HYSYS case file is created in version 2006. For the users of earlier versions, an XML file is also available.
If the objective is to have a user specified actual volume flow output, user can add another tee and an adjust unit to the flow. Set the value in cell D1 to ensure a higher actual volume flow in the stream Const Liq Vol Flow at Std Cond. Use the adjust unit to adjust the flow ratio of the second tee until one outlet has the desired actual volume flow.
User can also modify the example for multiple process streams or multiple makeup streams by adding streams to the mixer on the flowsheet and adjusting the flowrates in the spreadsheet Flow Settings.
Keywords: constant volume flowrate, acutal volume flow, spreadsheet, makeup, purge
References: None |
Problem Statement: Can I use HYSYS to model Liquid/Liquid contactors with the Amines Package? | Solution: HYSYS Version 2.3 and earlier versions did not have this capability.
Starting from version 2.4, this feature has been added into HYSYS, as a result of the incorporation of AMSIM v7.0. To model sour liquid sweetening process, please make sure to select the Li-Mather thermodynamics option when choosing your property package.
Keywords: Amines, Liquid-Liquid contactor, Li-Mather
References: None |
Problem Statement: Why is Molar Flow reported incorrectly when using HYSYS Stream Reporter (HSR) 1.6 with Aspen HYSYS 2004.2 and later? | Solution: The original HSR 1.6 was fully tested for Aspen HYSYS versions 3.2, 3.4 and 2004, but not for v2004.2 and later. The incorrect Molar Flow is reported in this version of the HSR due to the fact that the internal Unit Type for Molar Flow was changed from Flow in previous versions to Molar Flow in v2004.2.
The updated documents for the HSR (i.e. for Aspen HYSYS 2004.2 and 2006) are available in the originalSolution document # 110050. For convenience, the updated files are also attached herewith. Please download the new files when using the HSR 1.6 with Aspen HYSYS 2004.2 or later.
Keywords: HYSYS Stream Reporter, HSR, 2004.2, HSR excel file, 2006
References: None |
Problem Statement: When you simulate a liquid blowdown situation using the Depressuring utility, you sometimes see a message displayed for Vessel - Liquid Level Initialization with 3 options Increase Temperature, Non-Equilibrium Vapour or 100% Liquid. A screenshot of this message is included in the attached image file. Aspen HYSYS recommends users to use the Non-Equilibrium Vapour option. So what do these options mean? And why is the Non-Equilibrium Vapour option recommended? | Solution: First of all, this message is displayed when the vessel has no vapour phase at the specified process conditions. The following is a brief summery of what Aspen HYSYS will do under these options and suggestions on how to make your choice:
1) Increase temperature
What will happen: The initial temperature of the of the vessel contents will be increased until some vapour is formed. Essentially, the system will end up at the bubble point temperature.
When to use: If the vessel contains a multi-component mixture and you know the vessel is normally producing some gas. The initialization 'error message' may have occurred because the pressure in the vessel is just a bit higher in dynamics than in the steady state case, so the increase in temperature will be minimal.
2) 100% Liquid
What will happen: The vessel will be filled with liquid. The level will only drop once the integrator is running if there is some source of vapour connected to the vessel. Typically the vessel's vapour line is connected downstream to the atmosphere or to another volume filled with gas. In the case of being connected to the atmosphere, be careful to define the proper reverse flow conditions and composition in the product block of the boundary stream.
When to use: You would typically have a liquid like cooling water, crude oil or make-up liquid stored in a tank. In steady state simulation you don't care about the fact that such a tank has an air or nitrogen (or other gas) blanket over it because it is not part of the process. In dynamics, however, you need to model the blanket vapour. If you have taken this into account, you can use the 100% liquid option and the blanket gas will allow the liquid level to drop when the integrator is running.
3) Non-equilibrium vapour
What will happen: This option increases the temperature of the vapor phase so that it can exist. The liquid and vapor phases will have different temperatures when the integrator starts. You can put a small stream of N2 or CH4 in the steady state model so that there is some vapor present. This allows you to get a smooth start to the dynamic simulation, and then you can adjust the flow to zero once the integrator is going. You will get real results. If you block off the product vapor the level will slowly increase as the N2 is absorbed into the sub-cooled liquid. If you don't block off the product valve, you either get liquid going out the valve or reverse flow coming in (depending on the pressure of the vapor product). As noted in #2 above, it is important to set the composition of the product block to be what you expect (e.g. N2 if it is open to the atmosphere, CH4 for a fuel gas blanket).
When to use: As for #1, If the vessel contains a multi-component mixture and you know the vessel is normally producing some gas. The initialization 'error message' may have occurred because the pressure in the vessel is just a bit higher in dynamics than in the steady state case.
Also attached with thisSolution is an Aspen HYSYS file where a Depressuring utility is attached to a liquid stream. If you press the Run button for the Depressuring utility, you will be able to trigger the message mentioned above.
Keywords: Liquid blowdown, liquid level initialization, depressuring,
References: None |
Problem Statement: Why I cannot export the compositions of a stream from an spreadsheet according to | Solution: 114048?Solution
This can happen because Hysys is giving more or the same calculation level to the stream and it should be giving higher priority to the Spreadsheet calculation.
According to the Calculation Order in a Spreadsheet, for optimal performance spreadsheet cells should have their calculation levels set such that the calculation level increase with chained calculations. Imports should have the lowest calculation level, and exports should have the highest. Any cells that do calculations in between the importing and exporting cells should have their calculation levels set in between.
Changing the spreadsheet calculation level will set ALL cells to that value.
For changing the calculation level, please go to Simulation menu > Main Properties and a window like the following will come up:
As you can see the stream 1 and the Spreadsheet (SPRDSHT-1) have the same calculation level, so you are not going to be able to see the imported / exported results. In this way you have to change the Calculation level to the stream, for example to 400 and then you are going to be able to see the exported compositions from Spreadsheet.
Keywords: Compositions, Spreadsheet, calculation level
References: None |
Problem Statement: Why does Aspen HYSYS sometimes report slug flow with slug length greater than the pipe length? | Solution: The calculated slug length can sometimes cause conflicts (seeSolution ID 128568). According to thisSolution the slug length is the average length of the liquid pocket at the indicated frequency. The bubble length is the average length of the gas bubble at the indicated frequency. If the slug length is greater than the pipe length, then there is no slug flow in the pipe.
The slug tool in Aspen HYSYS calculates the stability of a stratified flow and in doing so assumes that the pipe length is infinite. This analysis is done at each location along the pipe and checks to find if small disturbances to the liquid height will increase and fill the pipe diameter. The slug tool then calculates the length of the slug and bubbles. The calculations only take the flow regime, flow stability and diameter of the pipe into consideration. It is independent of the length of the pipe, which is assumed to be infinitely long. If the slug length is greater than the pipe length, the slug flow will not occur along the entire length of the given pipe but the calculations are still presented by the tool.
Keywords: Slug Length, Bubble Length, Pipe Segment
References: None |
Problem Statement: How can I make a customized unit set as the default unit set? | Solution: Select the unit set and save it with a preference file.
For example, assume that you created a unit set of your own from cloning a HYSYS default unit set, changed the temperature unit to from degree C to degree K and left the rest unchanged. You named the unit set as My Unit Set. Whenever you open a HYSYS file, you would like to see that the temperature is displayed in degree K. To make this happen, here are the steps to follow:
To save My Unit Set with a preference file -
1. From the HYSYS top menu bar, select Tools and then Preferences.
2. On the Unit page of the Variables tab, highlight My Unit Set under Available Unit Sets.
3. Press the button at the left bottom corner of this view to Save Preference Set.
4. Provide a name, such as My Preference Set and then save it. Please make sure to keep the file extension unchanged, as .PRF.
To load My Unit Set with a preference file -
1. From the HYSYS top menu bar, select Tools and then Preferences.
2. Press the button at the right bottom corner to Load Preference Set....
3. Locate the preference file My Preference Set previously saved and press the Open button.
Please keep in mind that you don't need to repeat this procedure of loading preference file as long as you do not close your HYSYS application.
Keywords: Unit set, Preference file, customized, default unit set
References: None |
Problem Statement: How do I keep the PFD window in HYSYS maximized? When I open a Stream or Unit Operation, the PFD shrinks. | Solution: In HYSYS versions 2.4.2 and earlier, there was a limitation with having multiple maximized windows open at the same time. This has been fixed for HYSYS 3.0 and newer versions.
The workaround in HYSYS 2.4.2 and earlier versions is to grab the corner of the PFD and 'stretch' it to the desired size. Once this is done, the PFD will remain at that size, and will no longer shrink when streams and unit operations are opened.
Keywords: PFD, maximize, maximise, shrink, stretch
References: None |
Problem Statement: What is an MPC controller? | Solution: Model Predictive Control (MPC) refers to a class of algorithms that compute a sequence of manipulated variable adjustments in order to optimize the future behaviour of a plant. A typical MPC has the following capabilities:
1. Capable of handling multivariable systems with process interactions.
2. Encapsulates the behaviour of multiple Single Input Single Output (SISO) controllers and de-couplers.
3. Utilizes a process model, i.e., a first order model or a step response data is required.
4. Incorporates the features of feedforward control, i.e., must be measured disturbance by taking in consideration the model disturbances in its predictions.
5. Posed as an optimization problem and is therefore capable of meeting the control objectives by optimizing the control effort, and at the same time is capable of handling constraints.
MPC technology was originally developed to meet the specialized control needs of power plants and petroleum refineries, but it can now be found in a wide variety of application areas including chemicals, food processing, automotive, aerospace, metallurgy, and pulp and paper.
Keywords:
References: None |
Problem Statement: How can I get vapor pressure of a stream at stream temperature and pressure? | Solution: You can not calculate a vapor pressure at a Temperature and a Pressure. You can get vapor pressure only at a temperature. Because vapor pressure itself is the pressure at a particular temperature the liquid starts boiling.
The calculation procedure is simple.
Step 1: Delete the pressure of the stream (if there is any in the field).
Step 2: Specify stream Vapor Fraction as zero.
Step 3: Note down the calculated pressure from the stream's pressure field. It is the required vapor pressure.
Key Words
vapor (vapour) pressure, temperature and pressure
Keywords: None
References: None |
Problem Statement: Why does the LNG temperature cross occur even though Auto Prevent Temp. Cross option is checked in Aspen HYSYS Dynamics? | Solution: To use the function of Auto Prevent Temp Cross, it's suggested to specify at least 10 zones to stabilize the Temperature/flow (see Aspen HYSYS manual Unit Operation Guide). As a thumb rule you can have at least one zone for every 15 deg C change in temperature. If you still find instability issues, you can increase the number of zones.
You need to review the following:
1) On page Dynamics/Model, set the number of zones to 10. Then click Auto Connect button to set up the connection between each zones.
2) On page Dynamics/Specs, set DeltaP in each zone to 5KPa (or some reasonable number), then click Calculate k's to recalculate k-vale for each zones.
3) On page Rating/Sizing, set each zone geometry: width=0.20m, length=2, number of layers in set=2, repeated sets=10 (or some reasonable number).
4) On page Rating/Layers, set each zone properties same as the first layer's.
5) On page Rating/Heat Transfer, copy the first zone heat transfer information to other zones. Set Reach small split steps to 0.01, and Reach even split steps to 1.
Start the integrator. If the user prefers the number of zones to be one, the alternative way to avoid temperature cross is to either decrease U-value or increase Ref. flow rate. For example:
a) Change layer 0 Ref flow from 2e5 to 2e6 kg/h, and layer 1 ref. flow from 4e5 to 4e6 kg/h; or
b) Change layer 0 U from 1e4 to 2e3 kJ/h-m2-C, and layer 1 U from 4e3 to 5e3 kJ/h-m2-C
Run the integrator again to verify the temperature cross does not happen.
Note: Above numbers are used as an example. You need to use more reasonable numbers close to your actual model.
Keywords: Slug flow, pressure surge, Flow surge
References: None |
Problem Statement: How does ICARUS calculate Pipe Testing? | Solution: Pipe testing is a function of the number of fittings and valves, and whether the pipe itself is jacketed, not jacketed, or lined or not lined.
It is also a function of the pipe length and diameter.
The basis equation is as follows:
CONSTANT = 4 by default
if pipe is jacketed or lined, then the CONSTANT = 20
PipeISO = CONSTANT + (3.0) # of elbows + (4.0) # of tees + # of reducers + 3 of threadolets + (2.0) * # of valves.
Testing hours = 0.85 ((PipeISO 0.15) + (Diameter * Length / 130))
Keywords: pipe
testing
calculate
calculated
References: None |
Problem Statement: How does one select which streams are displayed in each Workbook tab? | Solution: To hide a stream:
1. Open up the Workbook and go to the tab of interest.
2. Right-click on the column pertaining to the desired stream and select Hide.
Alternatively:
1. Open up the Workbook and right click on the tab of interest.
2. Select the Order/Hide/Reveal menu option.
3. In the ensuing Order/Hide/Reveal Objects window, the list on the left shows the streams that are currently being displayed on the Workbook tab. To hide any of the streams in that list, highlight the stream name(s) and press the Hide button.
4. If there are any hidden streams (i.e. listed in the column on the right) that you wish to show, highlight the desired stream name(s) and press the Reveal button.
5. Click OK when you're finished.
Keywords: workbook, hide, streams, display, show, reveal
References: None |
Problem Statement: How to resolve Unable to load odbcji32.dll when trying to run interactive report | Solution: 1. Uninstall Microsoft Access Database Engine
On Windows 10 go to Settings > System > Apps & Features and search for access ...
Uninstall all versions of Microsoft Access Database Engine from your system.
On other systems use Uninstall or change Program or Repair or Remove Programs
Uninstall all versions of Microsoft Access Database Engine from your system.
2. Download and Re-install Microsoft Access Database Engine
§ Download the latest version of Microsoft Access Database Engine (2010) here:
http://www.microsoft.com/en-us/download/details.aspx?id=13255
Important: download the AccessDatabaseEngine.exe (not the _x64 version!)
§ Install the ODBC driver and retry.
If you still get the error Unable to load odbcji32.dll:
There are also known compatibility issues between 32bit ODBC drivers and 64bit versions of Microsoft Office.
It is recommended to install the 32bit version of Microsoft Office (instead of the 64bit version).
Also see related KB#146916.
Keywords: ODBC driver, odbcji32, ACCE, interactive report error, Microsoft Access installation, MS Office, Microsoft Access Database Engine 2010
References: None |
Problem Statement: The liquid level in my vessel is 97%, and I'm getting some liquid in the overhead vapor stream, Why is that? | Solution: The nozzles in Hysys are side ways, which means that if the liquid level rises such that the vapor space becames less than the nozzle diameter, the product stream will be two phase.
Keywords: Separator, Level, Nozzle
References: None |
Problem Statement: When there isn't any water in my stream, HYSYS has predicted the formation of hydrates. Why? | Solution: If water has not been included as a component in a stream or the stream water concentration is zero, HYSYS will perform hydrate formation prediction assuming the presence of free water.
Keywords: free water, no water, zero water concentration, hydrate
References: None |
Problem Statement: How does HYSYS calculate the Initial and Final Boilin Points (IBP and FBP) of my oil? | Solution: HYSYS uses the defaults of 1% and 98% for the IBP and FBP, respectively. With a 1% IBP value, HYSYS utilizes the boiling points of all components in the first volume percent of the given fluid and calculates a weighted average boiling point, which is used as the IBP for any further analysis. The final boiling point is determined in much the same way, using the weighted average of the boiling points for the components found in the final two liquid volume percent of the fluid.
To change these default values, go to the Simulation menu and choose Oil Output Settings. Or, you can go into the Basis Environment, and enter the Oil Manager, where you will find a button at the bottom for 'Oil Output settings'.
Keywords: Assay, IBP, FBP
References: None |
Problem Statement: Where does one specify the parameters for the Ergun equation in the Plug-flow reactor? | Solution: The Ergun Equation is a correlation derived by Ergun in 1952 for the calculation of the friction factor for a packed bed in a column as a function of Reynolds number. It is represented by:
f(p) = [150 / Re(p)] + 1.75
where f(p) and Re(p) are defined as:
f(p) = [Δp * D(p)] / [L * ρ * V(s)^2] * [(ε ^3) / ( 1 - ε )]
and
Re(p) = [D(p) * V(s) * ρ ] / [( 1-ε ) * μ ]
In the above equations:
Δp is the pressure drop across the bed
L is the length of the column
D(p) is the equivalent spherical diameter of the packing
ρ is the density of fluid
μ is the dynamic viscosity of the fluid
V(s) is the superficial velocity (i.e. the velocity of the fluid through the empty tube with the same volumetric flow rate)
ε is the void fraction of the bed.
Based on the properties of the fluid and the specifications of the packed bed reactor specified by the user, Aspen HYSYS has enough information to estimate the pressure drop using the Ergun equation. It is therefore not necessary to specify additional parameters for the plug-flow reactor.
Keywords: Ergun, Ergun equation, plug-flow reactor, PFR
References: None |
Problem Statement: How do I control the Calculation Execution Rate of a Spreadsheet? | Solution: On the Parameters Tab of the spreadsheet, there is a Dynamic Execution frame (top right corner). There are three check boxes in that frame which control when will the Spreadsheet be called for execution. You have the option to execute the spreadsheet
Before Pressure-Flow Step
After Pressure-Flow Step
Each Composition Step
Keywords: Spreadsheet
References: None |
Problem Statement: How do I get transport property data for the shell and tube side fluids as a function of the conditions in my heating and cooling curves in my heat exchanger? | Solution: The Property Table utility can be used to do this. You'll need one utility for the shell side and one utility for the tube side. The property table takes the composition of the stream and flashes at the conditions you specify. You can specify the range of temperature and pressure that you see in your heat exchanger. The transport properties are the dependent variables.
Go Tools Utilities and choose Property Table, press the select stream button and choose your shell or tube side feed stream. By default Temperature and Pressure are the two independent variables so you don't have to change these. Just enter the temperature and pressure range you are interested in. If your pressure is constant you can use State as the Mode. Please see the User's Guide documentation Section 8.12 for more information on the Property Table utility. Proceed to the Design Dep. Prop. page to choose your transport properties. Click on the appropriate radio button (for bulk, liquid, vapour etc) then click on the first cell under Property (HYSYS 2.1-2.2) and use the drop down menu to find your dependent property. Or in HYSYS 2.3 press the Add button and choose the Dependent property from the list. Press Calculate.
Keywords: viscosity, physical property curves, heat exchanger, cooling, heating, property table, heat capacity
References: None |
Problem Statement: What command line switches can I use with HYSYS? | Solution: These are all case insensitive.
Command
Function
/regserver
registers HYSYS for OLE Automation
/unregserver
unregisters HYSYS
/noregserver
skips registration (which is otherwise always done silently)
/BuildComselIndexFile
builds comsel.idx
/p<prefs filename>
sets preference file to be used
/s<script filename>
plays script at startup
/sx<script filename>
plays script and then exits HYSYS
/tl
run tasks using long-jumps (i.e. no threads like Win32s)
/tt
run tasks with threads (the default)
/ts
run tasks with threads but without any asynchronous tasks (i.e. PFD sync routing)
/runtime
tracks task runtime (internal for debugging)
/Automation or /Embedding
starts with app invisible (passed by OLE Automation clients)
/AutomationSingleUse
starts with app invisible and allows access to only one client (other clients start another copy).
/tn
where n is 0 through 9 affects the thread pooling. 0 means no pool (revert to standard one thread and semaphore per task). 1-9 sets the maximum number of uncommitted thread hosts in the pool after the pool has been fully compacted by the garbage collector. 3 is the default.
/nosplash
doesn't display the splash screen
The Start command allows other command line options that affect HYSYS. Some of these are:
Command
Function
/min
starts minimised
/max
starts maximised
/inv
starts invisible (not recommended)
Keywords: Command Line Switches
References: None |
Problem Statement: What does the Prevent Temperature Cross in Depressuring utility? | Solution: This feature is intended to balance the heat duties for two sections inside the heat zones to prevent the temperature cross. The heat transfer area factors between the two sections are automatically adjusted based on heat duties. In practical terms, it is designed to prevent a temperature cross between the fluid and the metal in cases where they are very close to each other. For example, if the fluid is 10 C and the wall is at 9 C the option is to prevent the fluid from going bellow 9 C. Depressurizing scenarios in any case are different however as there is a temperature drop due to the depressurizing itself. Essentially, it is only to be used if temperature crosses are actually detected. If there is no temperature cross then it would be recommended to keep it OFF.
Keywords: Prevent Temperature Cross, Dynamic Depressuring Utility
References: None |
Problem Statement: When modeling a Heat Exchanger in Dynamic Rating, is using Ft=1 a good approach? | Solution: When using the Dynamic Rating mode, the calculation mode is an integratedSolution, Aspen HYSYS splits the calculations among the heat exchanger and that's what it makes this mode more rigorous. In that way, Aspen HYSYS doesn't report the Ft correction factor, which is calculated as a function of the Number of Shell Passes and the temperature approaches but the user has to know that Aspen HYSYS for a counter-current heat exchanger set Ft as 1.0. and also for the Weighted method, Ft = 1, and as the Dynamic Rating mode is a good counterpart to the Weighted Model.
For more information about the Ft correction factor in other Heat Exchanger models in Aspen HYSYS please refer toSolution 121930.
For more information about the Heat Exchanger models please refer toSolution 109410.
Keywords: Ft, dynamic rating, weighted model
References: None |
Problem Statement: Why do I still get a warning about Not Enough Information for Pipe Calculation even when all the dimensions of the pipe segment have been specified? | Solution: The most likely cause is that you also need to specify some information about the heat transfer for the pipe. Check that your information supplied includes the ambient temperature.
Keywords: Pipe segment, not enough information, calculation
References: None |
Problem Statement: I am trying to add 'Methane' to my case, but when I type 'M', methane disappears off the component list. What should I do? | Solution: Depending on which list you are searching through, 'Methane' has a SimName of 'Methane', a FullName/Synonym of 'C1', and a Formula of CH4. Methane will only appear in the list when you type 'M' if the SimName radio button is On.
Keywords: component, add
References: None |
Problem Statement: My Column indicates a yellow status and a message saying High Liquid Level on Stages, what does that mean? | Solution: The liquid flow off any single tray is calculated using the Francis Weir equation:
LiqFlow = const LiqDensity WeirLength * [(Height of Liquid above weir)^2]
If the tray section weir length is too small, or the liquid flow down the column becomes too high, liquid starts to accumulate on the tray till the Height of Liquid above weir value is high enough to force as much liquids off the tray as the liquid to the tray and you get a warning indicating High Liquid Level on Stages.
If this happens in normal operation when your liquid load is reasonable, then you have to check your weir length. In Hysys weir length is supposed to be the summation of all weir lengths on the tray (or the tray section overall average if it changes from tray to tray). I.e. the weir length for a two path tray should virtually be twice that of a single pass tray and so on.
Keywords: Columns; high liquid level
References: None |
Problem Statement: Why I cannot change or edit the strip chart for the Depressuring Utility? | Solution: In order to:
Change the sampling interval
Remove variables from strip chart
Add variables to the strip chart
then one must either create a new strip chart with the desired attributes or modify an existing chart then re-run the depressuring utility. Any strip charts or variables added AFTER running the utility will not be viewable.
Note that more than one strip chart can be created for the same utility, thus it is important to label each chart appropriately so as to avoid confusion. In general, it is recommended to delete strip charts if they are not in use.
Keywords: strip chart, sampling interval, add variable, remove variable
References: None |
Problem Statement: Can I view all of the notes in my simulation in one place? | Solution: Beginning with HYSYS 3.0, all the user notes contained in a case can now be viewed from the Notes Manager dialog. The Notes Manager simplifies the search for notes written individual Unit Operations and Streams. The Notes Manager has advanced searching capabilities. The user can search through all the notes to find specific words or specific dates that the notes were written. The Notes Manager is accessed from the Flowsheet Menu.
Keywords: Notes Manager
References: None |
Problem Statement: What is the difference between HYSYS Upstream R2 and HYSYS Upstream R3 license? | Solution: The only difference between them is that with R2 you have access to black oil, but with R3 you DO NOT. If you have both in your machine it will try R2 first. Aspen HYSYS V7.3 can use either of them.
Keywords: HYSYS Upstream R2, HYSYS Upstream R3
References: None |
Problem Statement: My controller says INIT what does this mean? | Solution: The INIT box usually indicates that the OP value displayed on the controller has been back-calculated either from another controller or a selector block. The OP value is determined based on the Kc term and the PV range specifed on the controller.
A controller can show INIT under two circumstances:
1. The controller is the master controller in a master-slave configuration and the slave controller is not in cascade mode. The OP for the master controller is back calculated. This allows for bumpless transfer when switching controller modes. The INIT message serves to notify the user that the OP is being calculated elsewhere.
2. The controller is one of two (or more) controllers feeding their respective OPs into a selector block. The controller whose OP has not been selected will show INIT to indicate that it's OP has, in fact, been calculated by the selector. Again, this is to facilitate a bumpless transfer when the selected controller changes.
The attached two diagrams illustrate the two possible scenarios.
Keywords: cascade, controllers, INIT, slave, master, selector block
References: None |
Problem Statement: How do I add a new subflowsheet operation to my case using Automation? | Solution: The VBA procedure below (run this from Excel VBA) illustrates how to do this. The key lines are
Set hyNewTemplate = hyFlwSht.Operations.Add(strNewFSName, TemplateOp) hyNewTemplate.LoadTemplate
Set hyFlwSht = hyNewTemplate.OwnedFlowsheet
Where hyNewTemplate is declared to be of type TemplateOp and hyFlwSht is initially a Flowsheet object for the parent flowsheet.
The .LoadTemplate method can also takes an optional parameter to specify the location of an already existing template file, for example
hyNewTemplate.LoadTemplate d:\test.tpl
Note that the correct way to add a subflowsheet operation to a case is to start from the Flowsheet.Operations collection. Although it is possible to access existing subflowsheets from the Flowsheet.Flowsheets collection, the subflowsheet is actually owned by an operation which resides in the flowsheet. When you manually add a subflowsheet operation using traditional methods such as the Object Palette in the HYSYS GUI, you are adding the operation. Once the operation has been added, you will be prompted for what sort of flowsheet you will be adding (for example, importing a template or beginning with a blank flowsheet).
Public Sub AddNewSubFS()
'
'Description: Adds a new template / sub
flowsheet to the current flowsheet in the active
'
HYSYS case, Adds a few operations to it and links up streams to the main flowsheet
'
'Declare Variables--------------------
Keywords: None
References: None |
Problem Statement: What is the Acceleration factor on the Integrator window General tab? | Solution: The Acceleration factor is a way to increase the speed of the integration, thus speeding up the model. This is done through multiplying the acceleration factor by the step size to come up with the true step size used by the integrator. This is to say that increasing the acceleration factor above 1 is equivilant to using a bigger step size and it has the same effects on the model (i.e. it might introduce some disturbances for small capacitance systems).
Keywords:
References: None |
Problem Statement: My case used to use the Amines PP but I have changed it to something else and it's still asking for an Amines license. Why? | Solution: This is a bug in HYSYS 2.x that does not update the license requirement when you've changed from the Amines property package to something else.
The work around for this is:
Open the case, select all the objects in the PFD and export them to a file. Then, create a new case (with the same components & another PP such as Peng Robinson) and give the fluid package a name like test FP (you need to define a Fluid Package in order to go into the Simulation Environment).
Go into the Simulation Environment and import the flowsheet (the one that you just exported from the original case).
Go back to the Basis Environment and delete the test FP and reassign the case to use its original fluid package.
Keywords: amines, license
References: None |
Problem Statement: Where can I find the Properties Classes that are described in the Aspen HYSYS Thermodynamics COM Interface | Solution: If you need to program for COMThermo interface the objects are not available in the standard a??HYSYS 7.3 Type Librarya??.A You need to load a separate library.
Here is a list of the most common libraries mentioned in the reference guide:
Library Name:
Keywords: COMThermo, Library,
References: Guide? |
Problem Statement: How do I enter my distillation data ASTM D5236 in Aspen HYSYS? | Solution: Aspen HYSYS does not currently support D5236 standard. Aspen HYSYS does all calculations on a TBP basis in the Oil Manager. So, what is recommended to do is to find a software to convert D5236 into TBP or other standards which HYSYS can accept.
Another suggestion is that you review the testing procedure for your data and compare it to the ones accepted in HYSYS (TBP, ASTM D86, D1160, D2887). If it happens to be very similar to one of the procedures HYSYS recognizes, then it is up to you to decide whether it is close enough to use it as an alternative.
Keywords: D5236
References: None |
Problem Statement: How can I add component molar flows to a WorkSheet? | Solution: Make sure the WorkSheet that you want to add to is open and has focus. Choose the WorkBook option from the Menu Bar and then choose Edit Page. From the Edit Page view choose the Add button. From the Variable Navigator view that appears choose the Variable you want to add to the WorkSheet, in this case Component Molar Flow. Use the Single or All radio buttons to choose which components will have their Molar Flows displayed.
Keywords:
References: None |
Problem Statement: What do the Real Time and Real Time factor cells represent (on the Integrator window, General Tab) ? | Solution: If the the Real Time check box is checked it forces Hysys to run the model at real time, so one minute of the simulation time will correspond to one minute of real life.
The Real time factor cell is a measure of how fast the model is running and it is a factor between the simulation time and real time. So the higher the value the faster the model relative to real time.
Keywords:
References: None |
Problem Statement: The value of a user property (defined in the ‘User Properties’ folder) is not showing up in the Properties tab of some streams. | Solution: There may be several reasons for this occurrence. First, make sure that the referred property is activated for all streams in the flowsheet (this can be done accessing the Correlation Manager). Then, check the parameter Min. Def. Comp. (%) in the user-property tab in the Properties environment:
This parameter will restrict the property calculation to streams where the sum of the relevant components is above the indicated value. If you decrease this value to zero, then all streams should display a value for this property (where applicable).
Keywords: User Property, Min. Def. Comp., Correlation Manager
References: None |
Problem Statement: How do I get my reactive distillation column to converge? | Solution: If you are using the Sparse Continuation solver there are two things to quickly try.
Change from Rigorous to Pure on the 2/3 Phase page of the Parameters tab in the column view. When you treat the second liquid phase as Pure using the 3-phase solver, it allows simplification of the equilibrium calculations by assuming that the aqueous phase is pure water. Rigorous mode performs a rigorous calculation for the aqueous phase. We have seen cases which were difficult to solve immediately using a rigorous treatment of the second liquid phase. In such cases, the Pure option was used for an initial convergence. Once this initialSolution had been obtained, the column was able to converge after switching to the use of Rigorous.
AnySolution of a column obtained using the Pure option should, of course, be considered with due engineering judgement.
Ensure the basis for the reactant is the limiting reactant. The solver can manage the basis better this way. This may be the case with other solvers like Newton Raphson and Simultaneous Correction.
Keywords: sparse continuation solver, column, reactive distillation, converge
References: None |
Problem Statement: How do I resolve an unsuccessful DBR PVT Pro Exchange Package setup when using Windows 7? | Solution: Fix the registry error on the 64-bit machine, follow this steps.
1. Open the registry by opening the start menu and typing regedit in the Search programs and files field
2. Allow the program to make changes to the registry (requires administrative access)
3. Locate the key HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Hyprotech\Upstream\DBRPVTProPkg\Version 5.0 in the left pane
4. Right click on the string InstallLoc in the right pane and select Modify...
5. The original Data should be C:\Program Files\Common Files\Hyprotech\DBRPVTProPkg\Version 5.0, and it needs to be changed to the correct location of PVTProPkg.exe (which should be C:\Program Files (x86)\Common Files\Hyprotech\DBRPVTProPkg\Version 5.0)
Note: adjusting the registry can sometimes be dangerous if important keys are changed. Be sure that backups of data exist and that only the changes mentioned above are made.
Another way is to copy the whole DBR folder to Program file to the following path.
C:\Program Files\Common Files\hyprotech\DBRPVTProPkg
Keywords: PVT, environment, Schlumberger, launch, DBR, Windows 7
References: None |
Problem Statement: When I get the message saying: Error: Project evaluation failed in my trace Window what do I do? | Solution: This error is usually seen when you can get into the Design Tab, and you can use 'Check Design All Items' but when you go to run the Design Phase, you obtain the following error: *** Error: Project evaluation failed
You will need to check the following two items:
Ensure that your picasso.ini file (in the same directory as your HYSYS.exe) has all of the correct path designations within it.
You may have too long a path to the Economix data. For example, c:\program files\common files\hyprotech\icarus\JP1\projects\picasso\picasso.ccp is too long a pathname. You will need to uninstall the Icarus\JP1 software, and reinstall with a shorter path name, e.g. c:\icarus\JP1\. Then, you will have to uninstall and then re-install Hysys so that it will recognize the change in location of the JP1 software.
Keywords: Project Evaluation Failed, Economix,
References: None |
Problem Statement: What are the Product Block and Feeder Block buttons on the Dynamics Tab of a Stream? | Solution: A stream which has only one unit operation attached to it is called a flowsheet boundary stream. If a material stream is a flowsheet boundary stream, a Feeder block or Product block button is displayed in the Dynamics tab. A flowsheet boundary stream can be the feed or product of the model. Depending on whether the flowsheet boundary stream is a feed or a product, the Dynamics tab view displays either a Feeder block button or a Product block button.
The Product block button opens a view which displays flow reversal conditions of the material stream which the user can specify. If simulation conditions are such that the product stream flow becomes negative, HYSYS recalls the stream conditions stored in the Product block and performs a rigorous flash on the product stream to determine the other stream conditions.
When process conditions in the simulation cause the feed flow to reverse, the feed stream conditions are calculated by the downstream operation. The Feeder block is used to restore desired feed conditions and compositions if the feed stream reverses and then becomes feed again.
Keywords: Product, Feeder, Block, Boundary
References: None |
Problem Statement: Why, after interpreting Aspen HYSYS LNG multi-heat exchanging streams in Aspen Energy Analyzer (AEA), are the composite curves and/or HX-network optimization results different from those in Aspen HYSYS LNG? | Solution: When there is a pure component/azeotropic stream with a long phase change region and high pressure variations in the multi-heat exchanging streams of a plate fin exchanger, the Aspen HYSYS LNG unit operation could be used to generate composite results. However, after interpreting these streams in Aspen Energy Analyzer and running the case to generate composite curves, the resulting composite curves are sometimes different from those generated in Aspen HYSYS.
This is because Aspen HYSYS LNG uses the assumption of ''pressure varying with enthalpy,' whereas AEA uses the assumption of ?pressure varying with temperature.?
In case of a pure component/azeotropic model, temperature over the phase-changing region will be constant. AEA will assume the pressure over this region is constant too, whereas Aspen HYSYS will assume pressure still goes down along with the enthalpy change. Aspen HYSYS LNG?s treatment is more realistic, and should be used as much as possible. When generating composite curves, however, AEA?s assumption should be used, otherwise the composite curves might have below shapes, which cause non-monotonic composite curves hence making HX-network more difficult.
In such cases, the AEA method would be the only available option for HX-network analysis, and should be used.
Keywords: Composite Curve, Pressure varying with temperature, Pressure varying with enthalpy, AEA (Aspen Energy Analyzer), HYSYS, LNG, Plate Fin Exchanger
References: None |
Problem Statement: When I right click on a stream, I see the option Publish Stream. What is this? | Solution: Multiple HYSYS Cases can now be linked across multiple machines on a LAN or WAN. This is accomplished by linking the appropriate streams in a case with the streams of other cases. These links can be Live which means changes in the source stream are immediately and automatically transferred to the destination stream. Alternatively, the source stream changes can be manually transferred to the destination stream when the user requires the new information.
This new capability relies on the use of the Run-Time Integration (RTI) Server, which is installed with HYSYS 3.0. The RTI Server is the conduit through which the linked streams exchange data. Large plant wide HYSYS cases can now be broken into smaller more manageable cases and distributed to the engineers with expertise on the individual plant units. The entire model can then be linked together at the appropriate time to see the overall effect of the unit changes.
For more information on Case Linking, navigate to the HYSYS Knowledge Base Category Simulation | Case Linking / RTI Server
Keywords: Publish stream; link; RTI Server
References: None |
Problem Statement: Why does the Liq. Peak Flow display as empty in the Depressuring Utility? | Solution: The Depressuring Utility can be used to simulate the depressurisation of gas, gas-liquid filled vessels, pipelines and systems with several connected vessels or piping volumes depressuring through a single valve.
Keywords: Liq. Peak Flow, Depressuring, Liquid Flow Equation
References: s to vessel in this guide can also refer to piping or combinations of the two.
After you have specified all and the utility shows converged, if you go to the Performance> Summary and the window looks like the following:
But, you want to know the Liq. Peak Info and when you click it shows as empty like the following:
This is happening because you have specified only the vapor valve, so you need to add a Liquid Flow Equation in Design > Valve Parameters. In the first approach, you can customize a similar valve.
Sometimes, the step time should be low enough so that the end results do not depend on the step size taken. Also a smaller step time will allow capturing the peak flow. This can be set at the Operating Conditions page.
After that, please run your utility and after it founds a |
Problem Statement: How does the split feeds option for the column operation in Aspen HYSYS work? | Solution: When you double click on the column, the Flowsheet page of the column property view will contain the checkbox which will allow you to split feeds. The checkbox may show up on the Connections page, depending on whether you are running a column based on one of our templates (where you will see a diagram) or whether Aspen HYSYS considers your flowsheet a custom column (the template has been modified, and you will see a table with lists of streams, and no diagram).
When the split feeds option is not checked, all feed would enter stage 3 (for example) and contact the liquid on that stage. If you have 2 phases, the effect would be the same as the liquid part going directly to stage 3, and the vapour being fed to stage 4 and rising up to contact liquid on stage 3.
When the split feed option is checked, the liquid will go to the feed tray and the vapour will rise and contact the liquid on the stage above (which is generally closer to reality).
Note: the feed stream is always flashed at the feed stream pressure.
Be careful when using this option when you have streams consisting of only vapour (such as stripping steam for a crude column). Activating the Split Feeds checkbox splits all of the feed streams by default. Unless you have compensated for this when positioning your streams this may not be the correct setup.
Keywords: split feeds checkbox, column
References: None |
Problem Statement: How can I apply 'show table' option for all the streams? | Solution: You can select one stream and press 'shift' key from the keyboard and select the other streams of interest.
Once all the desired streams are selected, you can right click and pick 'show table'
Keywords:
References: None |
Problem Statement: How to find Henry coefficients and calculate the Henry constants. | Solution: Aspen HYSYS presents the Henry constant on the binary coefficient tab in the similation basis environment [Fluid Package | View | Binary Coeffs]. It is slightly confusing to read when you change the order of components [we recommend adding your non-condensable components first and then your condensable components]. Please refer to section A.3 page A-42 of Aspen HYSYS Simulation Basis manual (V7.1) for more details.
If you need further clarification you could compare the numbers with those found in Aspen Plus. [Please remember to check pressure units in Aspen Plus, when you scroll down to bottom, it should in kPa].
The attached PDF represents the Henery coefficient in Ln(x) form while Aspen plus and Aspen HYSYS values are in Ln(H) form. The equation:
Ln(x) + ln(H) = ln(101.325) can be used for comparison of Aspen Plus/ Aspen HYSYS and literature values.
Please refer to attached Excel files to see how the Henry coefficient is calculated in Aspen HYSYS and Aspen Plus.
Keywords: Henry, Henry Constant, Henry Coefficient
References: None |
Problem Statement: I am increasing scales on constraints to beyond the desired tolerance for the optimizer to find a feasible path. How do I ensure the optimizer meets my desired tolerances now that I increased the scales? | Solution: It appears as though it is sometimes necessary to increase the scales on constraints to beyond the desired tolerance in order for the optimizer to be able to find the feasible path. What can be done to ensure that the optimizer will be able to meet your desired tolerances when you are forced to increase scales?
Again, this relates to problems with feasibility. If you have to increase the scales, it is usually because the Optimizer cannot see a feasible region - which can be because there isn't one, the problem is very non-linear or it is very noisy.
With a well-presented problem - one with low noise, and an accessible feasible region - the Optimiser will converge on the appropriate constraints regardless of the size of the scale (unless they are too big, when it may pre-converge).
If you have to enlarge the scale to get anywhere at all, then you should rerun the problem starting from theSolution point with the original (tighter) scales back in place.
One difficulty that always causes distressful scaling symptoms, is where there is a discontinuity in one of the constraints or its derivatives.
Keywords:
References: None |
Problem Statement: HYSYS shows a tube or a shell outlet temperature that is different than what STX shows when STX is linked to HYSYS and it is on Rating mode. Pressure drops for both sides are transferred to STX as zero during the iterations when it is deleted on Design\ Parameters page in HYSYS. | Solution: When outlet pressure is not specified in HYSYS, the process conditions sent to STX are all based on inlet conditions. HYSYS then takes the calculated duty and pressure drop and re-calculates the temperature, in essence putting an isenthalpic valve after a zero pressure drop exchanger. The STX outlet screen shows the outlet temp of the zero pressure drop exchanger and HYSYS shows the temperature after the valve. HYSYS and STX temperatures are typically in very close agreement when an outlet pressure is specified.
Generally speaking, transferring zero pressure drops to STX has no effect on many cases (single phase liquids for example). It only affects cases where the heat curve may be affected by a change in outlet pressure or the vapor density is significantly different when the pressure drop is considered. As a rough guide when there is vapor or there are two phases, if the pressure drop is less than 10% of the inlet pressure you can assume that deleting the pressure drop specified on HYSYS Parameters page will work. You can always check the results by going back and specifying the pressure drop to confirm the results.
Keywords: STX
HYSYS
Link
Pressure drop
Outlet temperature
References: None |
Problem Statement: What does the content of the bracket mean in NBP[0] or NBP[2] etc? | Solution: Hypothetical components generated by the Oil Characterisation function in HYSYS are named as follows:
NBP[x]y
(E.g. NBP[0]28)
x is just a marker to indicate which oil blend the hypo belongs to. For example if in the Oil Characterisation Environment you set up two blends then the hypos belonging to the first blend will be called NBP[0] and the second NBP[1]. Each blend has its own set of hypos, they are not shared between blends.
y is the Normal Boiling Point (NBP) of the hypo. The units for y are those in use in HYSYS when the hypos are created. Hypo component names do not change if the units in use in HYSYS subsequently change. The only time they do change is if the hypos are regenerated (e.g. when you change one of the assays that goes to make up the blend).
Keywords: hypo, hypothetical, NBP, oil, blend
References: None |
Problem Statement: I have a palm pilot and a portable computer with only 1 port. How do I run Hysys with a standalone (green) key? | Solution: You have the following options:
If you have a HYSYS key on the same physical COM port as the Palm Sync Cradle, the following have been successful:
Place the Hotsync Manager in manual mode (via right-click, Setup, General Tab). This will close the Hotsync Manager and allow HYSYS to use the COM port. When you need to sync your PDA, start the Hotsync Manager (Hotsync.exe) manually and then sync your Palm. Remember to close the Hotsync Manager when complete.
Most of today's Hotsync utilities provide the ability to sync to either an IR port or USB port. You can free up your COM port for use with the HYSYS key by choosing either one of these two alternate syncronization optons.
HYSYS hardlock keys are also available that will connect to the Parallel port or USB port of your computer. You may request one of these replacement keys.
Note: Windows NT 4.0 does not support USB.
Keywords: Palm Pilot, Hot Sync Software, Serial Port, HYSYS, Green Key
References: None |
Problem Statement: How can I copy all the data from one stream to another on my flowsheet, using OLE? | Solution: The simplest means of doing this is to use code like:
Dim SourceStream As HYSYS.ProcessStream
Dim TargetStream As HYSYS.ProcessStream
'.... Need to establish objects for our streams here ....
TargetStream.SpecifyAsFluid SourceStream.DuplicateFluid
This will specify T, P and molar flow in the Target Stream regardless of what conditions were specified / calculated in the source stream. What the code is actually doing is creating a Fluid Object from the SourceStream object then passing this to the TargetStream.
If you want to specify what kind of data is specified in the target stream (eg PT flash, PH flash .... and what kind of flow rate is specified), then these values must be explicitly set.
Attached is an Excel file with some example VBA code that illustrates how this might be approached.
Keywords: OLE, Automation, Copy Stream, SpecifyAsFluid, DuplicateFluid
References: None |
Problem Statement: How do you enter the tube length and number of tubes for a U-tube exchanger in Aspen HYSYS? | Solution: The number of U Tubes specified should be the ACTUAL number of U-tubes, NOT the number of holes in the tubesheet (which is 2x the number of tubes).
The tube length entered should be the total length of the U-tube, including the U bend.
Keywords: u-tube, u tube, beu
References: None |
Problem Statement: How do I change default K values (Distribution coefficients) displayed on the worksheet tab for a given stream? | Solution: On the simulation basis manager go to the fluid package tab, open/view the fluid package in which you want the distribution coefficients to be changed.
Go to tabular tab and enable tabular properties.
Go to options branch and select the checkbox of the property you want to modify
Finally go to information branch, the previous property will appear now and you can change the parameters there.
For more information about this option reffer to the Simulation Basis Manual, section 2-71.
Keywords: k values, distribution, coefficient, tabular, simulation basis.
References: None |
Problem Statement: Why does the Icarus cost engine increase the number of plates for a column imported from a simulation? | Solution: Icarus increases the number of plates if tray efficiencies are not specified in the simulation. ]
When this happens, the Icarus cost engine will assume the default efficiency specified in Process Design ->Design Criteria, and the default is 0.6. (The cost engine will calculate the Actual No. of stages = No. of Theorectical stages/Tray Efficiencies).
For example, if there are 20 stages in the simulation, the Icarus cost engine will calculate the stages using 20 stages/0.6 = 33.3. This value the gets rounded up to 34 stages.
If user wishes the Icarus cost engine to have 20 stages, he can do so by changing the default value from 0.6 to 1.0 in Process Design -> Design Criteria.
Keywords: Column, Number of trays, Import, Simulation, plates
References: None |
Problem Statement: Tips for running Gas Pipe in Aspen HYSYS Dynamics | Solution: For simplicity and more pressure drop correlations, it is recommended to use Aspen HYSYS pipe segment. The CGP unit operation is primarily designed for transient calculations with streams. Steady state calculations have been implemented primarily for initialization of the Pipe State prior to transient calculations. But if you want to use Gas Pipe, following information will be useful.
1. Always have a valve before and after the Gas Pipe to help the Gap pipe solver integrate with Aspen HYSYS solver. Give a small pressure drop (5kpa).
2. You need to look at every single unit individually. There is a tuning process of the number of cells to get convergence. The minimum is 10, go to the Rating, Sizing page and adjust it depending on whether or not the internal profiles are more or less flat. With regard to the integrating step size, the larger the number of cells, the smaller it has to be.
3. When using CGP model, the user must pay attention to integration step size. The default step size of 0.5 second cannot solve the model. It will depend on problem type, but at least 0.01 second (or smaller) should be used.
Decide what is the maximum time step size you can have: Find the maximum velocity (say: 37 m/sec) of the fluid in one cell (click view profile) and cell length (10m) on the Performance tab Profile page. Calculate how much time (0.27 sec) fluid will take to pass through one cell. Make sure the flash calculation is performed at least 4 times in that cell (It will do composition flash at 10th time step by default). So if the default time step is 0.5 sec, it will do the flash calculation every 5th second. For4Xflash calculation, it will need 20 sec. As per current fluid residence time, the fluid will only flow for 0.27 sec in one cell. So your time step size should be reduced below 0.0135 sec (0.27/20).
4. To capture the effects of enthalpy changes due to pressure, the Table Interpolation method should be used for the property method of the compressible gas pipe. The perfect gas and compressible gas models assume that enthalpy is only a function of temperature so the pressure effects will not be captured using these models.
Note: The gas pipe model and the PF solver can NOT solve simultaneously, the gas pipe has to contribute some equations to the PF solver, and the way it does that can cause conflicts. To solve the gas pipe move the P spec to the Product stream and the F spec to the Feed. The Compressible Gas Pipe does not support an energy stream. CGP calculates the speed of sound and Mach number that is not available in Pipe segment.
Keywords: Gas pipe, Dynamics
References: None |
Problem Statement: How do I enable a User Variable on all streams / operations? | Solution: In order to enable a user variable on all streams / operations without going through each stream / operation individually, go to the Attributes tab on the User Variable editing window of the User Variable. (If no tabs are visible, click the downward pointing green arrow at the top right hand corner of the window) Now change the Activation radio button to Automatic - the user variable will be enabled on all streams / operations.
Keywords: User Variables, Automatic, Activation
References: None |
Problem Statement: How is the Latent Heat of Vaporization calculated in Aspen HYSYS? | Solution: The Latent Heat of Vaporization of a pure component is defined as the molar/mass enthalpy change occurred when it changes state from a saturated liquid to a saturated vapor, at constant pressure. In Aspen HYSYS, the Heat of Vaporization of a mixture is defined as the enthalpy difference between the bubble point and the dewpoint at a fixed pressure. Therefore the Heat of Vaporization of a mixture is higher than the Heat of Vaporization of the individual pure components due to the fact that mixing effect is considered and that additional energy is required to raise the temperature to the dewpoint (sensible heat).
In general, the Heat of Vaporization is not reported if Aspen HYSYS cannot perform either the bubble point or dewpoint calculation. For example, above the critical point (e.g. in the dense phase), the saturated vapor (dewpoint) and liquid (bubble point) do not exist and therefore the Heat of Vaporization is not meaningful.
Keywords: latent, heat, hov, vapourization, vaporization
References: None |
Problem Statement: I have a simulation file which seems to be converged. However, Aspen HYSYS still displays error message(s) indicating Correlation Recall problems. What should I do? | Solution: The correlation recall problem can be eliminated simply via the correlation manager. From the top level menu, select Tools | Correlation Manager. First, look at the Messages tab to find out what Aspen HYSYS is complaining about. In the attached image file, Correlation recall problems.TIF, you can see, as an example, the screen-shot from a simulation file. To get rid of the error message(s), please do the following:
1. Check the View check-box under Recall Problems at the bottom right corner of the Correlation Manager view. You will note that when you do this, the matrix on the left side of the window updates all invalid stream correlations. From this updated list, you can individually delete the offending correlations, OR
2. You can simply click the 'Delete all invalid correlations from this case file' icon and automatically remove all invalid correlations from the case. Note that this icon is located just below the aforementioned matrix, and looks like three red X's grouped together, as shown in the second image file Delete all invalid correlations.TIF attached herewith.
3. Save your Aspen HYSYS file.
Keywords: recall, correlation, correlation manager, error, errors, message, inactive
References: None |
Problem Statement: How do I copy text from one PFD to another? | Solution: If your text is only one line long, this is easy. Just open the text box in the PFD you want to copy from and select the text, press Ctrl-C (for copy). Close the window and load the case (or PFD) you want to copy to. Insert a text box and simply hit Ctrl-V (for paste) inside the box.
If your text is multiple lines long, you can try the following steps (in v2.2+). For older versions, this will not work. Note that a more general cut/paste text feature has been included in the wish list for HYSYS.
For multiple lines of text:
Copy the text from the PFD using Ctrl-C
Open Microsoft Word (or Word Pad, although Word works better).
Paste the text in to an empty document. Save the document
Open your PFD in the case you want to paste into. Right click on the PFD and choose insert object.
Go to the Create from File page. Browse to find the Word document you just created.
Press OK. The document is now on the page. However, as a text editing document includes extra space at the end of the lines, the text box is larger than it needs to be. There is no quick and easy way to remove the extra space at this time.
Keywords:
References: None |
Problem Statement: How do I choose between the Li-Mather and Kent-Eisenberg Models for the Amines Package? | Solution: The creators of the Amines property package, DBR, have the following recommendations:
The Li-Mather model is recommended to be used for two amine systems and/or systems which are expected to fall outside the operating ranges recommended in the manual.
The Kent-Eisenberg model is recommended for single amine systems and/or those systems which fall inside the operating ranges recommended in the manual.
LM and KE can both be used for gas or liquid treating, however, LM appears to be better for liquid treating. Keep in mind that Hysys 2.4.1 does not model liquid treating properly with either model, and should not be used. This is fixed for Hysys 3.0. The KE model uses an ideal liquid phase model and the Li-Mather model uses a non-ideal liquid phase model.
Please reference Appendix C in the Simulation Basis manual for more information on the Amines package.
Keywords: Amine, KE, Kent-Eisenberg, LM, Li-Mather
References: None |
Problem Statement: How do I add components in a HYSYS case? How do I view fluid properties? | Solution: Please see attached document.
Keywords: components; fluid properties
References: None |
Problem Statement: A Process Simulator File (PSF) contains both process and physical property data that enables data generated by a program (normally a process simulator) to be transferred to an Exchanger Design and Rating (EDR) program. This knowledge base article describes the steps to create a PSF in Aspen HYSYS. | Solution: Attached is an extension which generates Aspen Exchanger Design & Rating (EDR) process input (PSF) files from an Aspen HYSYS simulation case that contains heat exchanger unit operations. To use this utility, you need only have Aspen HYSYS installed.
The procedure to create a PSF file from Aspen HYSYS is as follows:
1. Install the program attached to thisSolution
Unzip into a folder, and then run SETUP.EXE', click 'OK' and follow the on-screen instructions.
2. Run the program
From the 'Start' menu on the task bar, select 'Run' and in the Run dialog box use browse to select 'HTFSpsf.exe' and click 'OK' or using Windows Explorer select your chosen directory and double click on the HTFSpsf icon or program name.
3. Generate a PSF input file
Click on the browse button to enable you to open an Aspen HYSYS simulation case (*.hsc). The program will then automatically start Aspen HYSYS (if it is not already running) and load the case. The simulation is then scanned for heat exchangers.
A list of heat exchangers is shown and you can select any one of these. The temperatures and pressures for the streams are summarized. When you click OK the program will generate a PSF file and display the contents. You can then save this or print it as required.
It is possible to change the temperatures an pressures. This does not affect the Aspen HYSYS case but does let you change the range of temperatures considered.
Note: The extension provided is for academic purposes only and as such are not subject to the quality and support procedures of officially released AspenTech products. Users are strongly encouraged to check performance and results carefully and, by downloading, agree to assume all risk related to the use the extension. We invite any feedback through the normal support channel at [email protected].
Keywords: EDR input file generator, psf
References: None |
Problem Statement: How can I make a customized unit set as the default unit set? | Solution: Select the unit set and save it with a preference file.
For example, assume that you created a unit set of your own from cloning a HYSYS default unit set, changed the temperature unit to from degree C to degree K and left the rest unchanged. You named the unit set as My Unit Set. Whenever you open a HYSYS file, you would like to see that the temperature is displayed in degree K. To make this happen, here are the steps to follow:
To save My Unit Set with a preference file -
1. From the HYSYS top menu bar, select Tools and then Preferences.
2. On the Unit page of the Variables tab, highlight My Unit Set under Available Unit Sets.
3. Press the button at the left bottom corner of this view to Save Preference Set.
4. Provide a name, such as My Preference Set and then save it. Please make sure to keep the file extension unchanged, as .PRF.
To load My Unit Set with a preference file -
1. From the HYSYS top menu bar, select Tools and then Preferences.
2. Press the button at the right bottom corner to Load Preference Set....
3. Locate the preference file My Preference Set previously saved and press the Open button.
Please keep in mind that you don't need to repeat this procedure of loading preference file as long as you do not close your HYSYS application.
Keywords: Unit set, Preference file, customized, default unit set
References: None |
Problem Statement: How do I keep the PFD window in HYSYS maximized? When I open a Stream or Unit Operation, the PFD shrinks. | Solution: In HYSYS versions 2.4.2 and earlier, there was a limitation with having multiple maximized windows open at the same time. This has been fixed for HYSYS 3.0 and newer versions.
The workaround in HYSYS 2.4.2 and earlier versions is to grab the corner of the PFD and 'stretch' it to the desired size. Once this is done, the PFD will remain at that size, and will no longer shrink when streams and unit operations are opened.
Keywords: PFD, maximize, maximise, shrink, stretch
References: None |
Problem Statement: What is an MPC controller? | Solution: Model Predictive Control (MPC) refers to a class of algorithms that compute a sequence of manipulated variable adjustments in order to optimize the future behaviour of a plant. A typical MPC has the following capabilities:
1. Capable of handling multivariable systems with process interactions.
2. Encapsulates the behaviour of multiple Single Input Single Output (SISO) controllers and de-couplers.
3. Utilizes a process model, i.e., a first order model or a step response data is required.
4. Incorporates the features of feedforward control, i.e., must be measured disturbance by taking in consideration the model disturbances in its predictions.
5. Posed as an optimization problem and is therefore capable of meeting the control objectives by optimizing the control effort, and at the same time is capable of handling constraints.
MPC technology was originally developed to meet the specialized control needs of power plants and petroleum refineries, but it can now be found in a wide variety of application areas including chemicals, food processing, automotive, aerospace, metallurgy, and pulp and paper.
Keywords:
References: None |
Problem Statement: How can I get vapor pressure of a stream at stream temperature and pressure? | Solution: You can not calculate a vapor pressure at a Temperature and a Pressure. You can get vapor pressure only at a temperature. Because vapor pressure itself is the pressure at a particular temperature the liquid starts boiling.
The calculation procedure is simple.
Step 1: Delete the pressure of the stream (if there is any in the field).
Step 2: Specify stream Vapor Fraction as zero.
Step 3: Note down the calculated pressure from the stream's pressure field. It is the required vapor pressure.
Key Words
vapor (vapour) pressure, temperature and pressure
Keywords: None
References: None |
Problem Statement: Why does the LNG temperature cross occur even though Auto Prevent Temp. Cross option is checked in Aspen HYSYS Dynamics? | Solution: To use the function of Auto Prevent Temp Cross, it's suggested to specify at least 10 zones to stabilize the Temperature/flow (see Aspen HYSYS manual Unit Operation Guide). As a thumb rule you can have at least one zone for every 15 deg C change in temperature. If you still find instability issues, you can increase the number of zones.
You need to review the following:
1) On page Dynamics/Model, set the number of zones to 10. Then click Auto Connect button to set up the connection between each zones.
2) On page Dynamics/Specs, set DeltaP in each zone to 5KPa (or some reasonable number), then click Calculate k's to recalculate k-vale for each zones.
3) On page Rating/Sizing, set each zone geometry: width=0.20m, length=2, number of layers in set=2, repeated sets=10 (or some reasonable number).
4) On page Rating/Layers, set each zone properties same as the first layer's.
5) On page Rating/Heat Transfer, copy the first zone heat transfer information to other zones. Set Reach small split steps to 0.01, and Reach even split steps to 1.
Start the integrator. If the user prefers the number of zones to be one, the alternative way to avoid temperature cross is to either decrease U-value or increase Ref. flow rate. For example:
a) Change layer 0 Ref flow from 2e5 to 2e6 kg/h, and layer 1 ref. flow from 4e5 to 4e6 kg/h; or
b) Change layer 0 U from 1e4 to 2e3 kJ/h-m2-C, and layer 1 U from 4e3 to 5e3 kJ/h-m2-C
Run the integrator again to verify the temperature cross does not happen.
Note: Above numbers are used as an example. You need to use more reasonable numbers close to your actual model.
Keywords: Slug flow, pressure surge, Flow surge
References: None |
Problem Statement: How does ICARUS calculate Pipe Testing? | Solution: Pipe testing is a function of the number of fittings and valves, and whether the pipe itself is jacketed, not jacketed, or lined or not lined.
It is also a function of the pipe length and diameter.
The basis equation is as follows:
CONSTANT = 4 by default
if pipe is jacketed or lined, then the CONSTANT = 20
PipeISO = CONSTANT + (3.0) # of elbows + (4.0) # of tees + # of reducers + 3 of threadolets + (2.0) * # of valves.
Testing hours = 0.85 ((PipeISO 0.15) + (Diameter * Length / 130))
Keywords: pipe
testing
calculate
calculated
References: None |
Problem Statement: When I print my PFD, a bunch of overlapped letters are shown in the bottom of the sheet, how can I take them away? | Solution: This might be because the path to the file in your machine is extremely long, so the letters could overlap and it's not going to look good as you can see below:
There are two ways to take this away:
1. As this is caused by the large path in your machine in which the file was saved, you can try to save it in a much shorter patch such as your desktop and also you can try to reduce the name of the file and the issue will be gone, as you can see below:
2. If you cannot modify the path of the file, you can modify your PFD print in third party software such as Microsoft One Note or AutoCAD
a. Send to One Note
i. Please right click on the main PFD and select Print Setup and choose ''Send to One Note''
ii. Please right click on Print PFD and be sure that the Microsoft One Note is open and then select the part in which you want to add the PFD
iii. It can look like the following and to take away the footer you can simply edit the PFD in there.
b. AutoCAD
i. Please right click on the main PFD and select Print PFD to File and then choose Print DXF file as you can see below:
ii. According to theSolution 109054 to select the information to be printed to the DXF file, first select Setup DXF. By default, all the information is selected. The DXF output is the information in the flow sheet on the currently displayed PFD tab.
iii. Once that is saved it like that, you can open your file using AutoCAD and customize your printing, in that way you can erase the path of the Hysys file.
For more information you can take a look on theSolution 121496
Keywords: Print PFD, large path, AutoCAD, Microsoft One Note
References: None |
Problem Statement: How can I enter Basic and Detail Engineering as a lump sum cost? | Solution: If you want the basic engineering going to one contractor, you will have to set up workforces under Engineering Workforce - By Discipline.
First, give each workforce a number. Here is an example:
Once you set up those workforces, then go back into Engineering Workforce - By phase, and specify the workforce number like this:
Once you finish with that, then you must link those workforces to the appropriate contractors.
For example, if you want Basic Engineering to be performed by Contractor #2, then you need to go Contracts - Contractors and link the BASIC workforce to Contractor number 2.
Once you do this, then the numbers will come out as you expect in the Contractor reports.
Keywords: lump sum, workforce
References: None |
Problem Statement: Where can I find I/O information in my output report? | Solution: The I/O information is located in the .CCP report in the section called MATERIAL AND MANPOWER SUMMARY - INSTRUMENTATION.
Remember, you need to specify a digital control center (DDCTL) (Process Control - CTL) in order to get I/O counts.
Keywords: I/O, ccp, material and manpower summary - instrumentation, i/o, digital
References: None |
Problem Statement: How can I merge multiple HYSYS cases into one case? | Solution: Pick one case that you want to be the main case.
Open one of the other cases and convert them to a template (Simulation menu, Main Properties option, Convert to Template; you can find more information about this process in the User's Guide, chapter 2).
Convert the other case(s) to templates.
Open the main case and add a sub-flowsheet unit op. When you add this, HYSYS will ask you if you want to use an existing template or a blank one. Select to use an existing template and select the template you want. Repeat with the other templates.
Keywords: merging files, mutiple files, convert to template
References: None |
Problem Statement: How do I add an annotation to a PFD? | Solution: A? Use the letter A on the PFD toolbar to enter Annotation.
A? A Text Box will appear. You can enter the desired text.
A? Press OK key once you finish entering the Annotation.
A? To edit the annotation, right-click on the typed annotation to pick view properties.
A? To change the font/color, right-click on it and pick what you want to do.
Keywords: interface, text
References: None |
Problem Statement: When I click on an item such as a stream on my PFD, I get a Hysys message of CLIPBOARD OPERATION FAILED or CLIPBORAD COPY IS NOT IMPLEMENTED. Why? | Solution: Typically, this message appears when a copy/paste function has failed.
However, in the first case (CLIPBOARD OPERATION FAILED) it was found that the source of the problem was a conflict between Aspen HYSYS and the software iFinger French-English auto-dictionary of Hachette-Oxford. The iFinger also conflicts with many other softwares including Word. When iFinger is removed everything is normal.
In the second case (CLIPBOARD COPY IS NOT IMPLEMENTED), a conflict was found with a program called Concise Oxford Dictionary (Tenth Edition). This has an option to Watch clipboard and respond to double clicks. When this option is unchecked the problem is solved.
Keywords: Clipboard Operation Failed, Clipboard, Error, iFinger
References: None |
Problem Statement: How can I calculate a stream Dew or Bubble Point in Dynamics? | Solution: In steady state this could be easily accomplished using a Balance operation - however this is not possible in Dynamic operation.
In the attached case the mixer operation has a User Variable (Design Tab ... User Variables page ...) that calculates the stream temperature if it were flashed at the same pressure to have a vapour fraction as specified in the Vapour Fraction user variable.
To see this in operation.
Switch to Dynamics mode
Start the Integrator
A new user variable called Vapour Fraction is added to the mixer - by default this is set to 1 to give a dew point temperature. Adjusting this value sets the vapour fraction in the flash (e.g. changing it 0 would give a bubble point temperature).
Also attached is a file (DynDewBubblePtUv.huv) that can be use to import the user variable into any other Hysys case.
To do this ....
Go to the menu option Simulation ... Import and Export User Variables Press the Select File button and navigate to the DynDewBubblePtUv.huv file on your computer Select it and press OK
The file name should now appear in the right-hand list box
Press the import button - the user variable should now appear in the listboxes on the left-hand side. (i.e. Mixer and ProdTatGivenVapFrac) Press OK
For any stream that needs to have a dew or bubble point calculated a dummy mixer must be included (as in the example case)
Go to the Design Tab .. User Variables page of the dummy mixer
The user variable may already appear in the list - if it doesn't, press the green tick button at the top right of the window, it should now appear.
To enable the user variable check the checkbox next to it's name.
When the Integrator is next run the Vapour Fraction user variable should also appear.
Keywords: Dynamics, User Variable, Dew Point, Bubble Point
References: None |
Problem Statement: Can I output my PFD to AutoCAD? | Solution: Yes. This can be done by right clicking on the PFD and choosing Print PFD to File and Print to DXF File. To select the information to be printed to the DXF file, first select Setup DXF. By default, all the information is selected. The DXF output is the information in the flowsheet on the currently displayed PFD tab. If there are more than 1 pane associated with the PFD tab it makes no difference to the size or zoom factor of the DXF output.
Keywords: export PFD, AutoCAD
References: None |
Problem Statement: What does Ice Forms First mean? | Solution: It means that HYSYS predicts that ice will form before the formation of hydrate. When this is the case, HYSYS will not report a hydrate formation temperature.
Keywords: ice form first, hydrate
References: None |
Problem Statement: How to calculate pipe segment flow rate in Aspen HYSYS and Aspen Hydraulics by specifying inlet and outlet pressure. | Solution: 1. Calculate flow rate in the Aspen HYSYS main flowsheet.
In Aspen HYSYS, Pipe Segment contains four calculation modes: Pressure Drop, Length, Flow and Diameter. In order to calculate flow rate, we need to provide:
a. Pipe Geometry: pipe length and diameter
b. Heat transfer information
c. Inlet & Outlet Pressure of the pipe (or one stream pressure and pressure drop)
d. One stream temperature
A A A A A A A A A A A A A Calculation chart:
2. Calculate flow rate in Aspen HYSYS Hydraulics sub-flowsheet.
From Aspen HYSYS V7.3, a variety of boundary conditions are applied to Aspen Hydraulics flow network.
Scenario
Inlet Pressure
Outlet Pressure
Mass Flow
1
Calculated
Specified
Specified
2
Specified
Specified
Calculated
3
Specified
Calculated
Specified
By specifying two variables as boundary conditions, the third unknown variable can be calculated.
To carry out the flow rate calculation in Hydraulics, one additional input, i.e.
Keywords: Pipe Segment, Flow rate, Hysys, Hydraulics
References: temperature of the outlet stream, is needed to help the convergence.
Please see the attached Hysys file. |
Problem Statement: How do I prevent the error message Your Preference File is out of date or corrupted. It has been reset. | Solution: If you have multiple versions of Aspen HYSYS installed in your computer this could cause the corruption of one of your files for one version. If this is preventing you from using HYSYS without crashing you can repair it by going to your preference folder, located at: C:\Users\#My User#\AppData\Roaming\AspenTech.Â
If HYSYS is open, you will need to close it and then delete the file corresponding to your version. Next time you open HYSYS it will create a well formatted preference file with the extension *.PRF
Keywords: Preference File, PRF, Crash
References: None |
Problem Statement: How do I access gas properties correlation data from VBA code? | Solution: The stream gas properties correlation values can be accessed by the function called GetCorrelationValue(parameters).The parameter names are those shown in the correlation picker table as shown below. This code is applicable for Aspen HYSYS V7.2 and higher.
The code segment to access the gas properties correlation values is given below.
' Code to access properties correlation from VBA
Option Explicit
Dim hyApp As HYSYS.Application
Dim hyCase As SimulationCase
Dim hyStream As ProcessStream
Dim hyRealVariable As HYSYS.RealVariable
'General process variables
Dim hhvmas, hhvmol, hhvvol, lhvmas, lhvmol, lhvvol, masden, wcont, wdew, hcdew, wi As Double
'Link to HYSYS application
Set hyApp = GetObject(, HYSYS.Application)
'Get the case currently open
Set hyCase = hyApp.ActiveDocument
'Working with HYSYS stream
Set hyStream = hyCase.Flowsheet.MaterialStreams(StreamName)
'Get higher heating value on mass basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Mass Basis, Gas)
hhvmas = hyRealVariable.Value
'Get higher heating value on mole basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Molar Basis, Gas)
hhvmol = hyRealVariable.Value
'Get higher heating value on volume basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Vol. Basis, Gas)
hhvvol = hyRealVariable.Value
'Get lower heating value on mass basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Mass Basis, Gas)
lhvmas = hyRealVariable.Value
'Get lower heating value on mole basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Molar Basis, Gas)
lhvmol = hyRealVariable.Value
'Get lower heating value on volume basis
Set hyRealVariable = hyStream.GetCorrelationValue(HHV Vol. Basis, Gas)
lhvvol = hyRealVariable.Value
'Get water content
Set hyRealVariable = hyStream.GetCorrelationValue(Water Content, Gas)
wcont = hyRealVariable.Value
'Get water dew point
Set hyRealVariable = hyStream.GetCorrelationValue(Water Dew Point, Gas)
wdew = hyRealVariable.Value
'Get HC dew point
Set hyRealVariable = hyStream.GetCorrelationValue(HC Dew Point, Gas)
hcdew = hyRealVariable.Value
'Get Wobbe Index
Set hyRealVariable = hyStream.GetCorrelationValue(Wobbe Index, Gas)
wi = hyRealVariable.Value
Please refer KBSolution 112361 for more information on VBA automation for linking Excel to Aspen HYSYS.
Keywords: Properties Correlation, GetCorrelationValue, VBA
References: None |
Problem Statement: How do I enter ASTM D7169 in Aspen HYSYS Oil Manager or in Aspen HYSYS Petroleum Refining? | Solution: This test method extends the applicability of simulated distillation to samples that do not elute completely from the chromatographic system. This test method is used to determine the boiling point distribution through a temperature
of 720C. This temperature corresponds to the elution of n-C100.
Oil Manager in HYSYS or Macrocut table in HYSYS Petroleum Refining (RefSys) do not have option to select ASTM D7169. Input this type of data data as TBP on mass basis.
Keywords: ASTM D7169, 7169, D7169
References: None |
Problem Statement: For a 3-phase flow problem (oil, gas and water), does Aspen HYSYS calculate separate oil phase and aqeous phase velocities? | Solution: When a 3-phase correlation (Tulsa Unified Model 3-phase or OLGAS_3P) is used, separate oil phase and aqueous phase velocities are calculated. For all the other two-phase correlations, the oil and aqueous phase are combined into a single liquid phase.
Keywords: a 3-phase flow, pressure correlations, phase velocity
References: None |
Problem Statement: What would be the best approach to model a system with MEG, water and some light hydrocarbons in Aspen HYSYS? | Solution: When modelling a process in Aspen HYSYS the first and probably the most important step of the simulation process is the selection of the property package.
One of the limitations when selecting HYSYS Peng-Robinson (independently whether the pressure of the system is above 10 bar) is that there are some missing binary interaction parameters (BIP) for the system EG/hydrocarbons or supercritical components such as CO2.
Considering a low pressure system (below 10 bars), the best approach would be using an activity coefficient model such as NRTL or UNIQUAC. However, instead of specifying this method from the HYSYS database, the recommendation is to use Aspen Properties in HYSYS. The reason for this recommendation is that Aspen Properties is a stand alone software that allows the user to use experimental data to regress Binary Interaction Parameters or use the Estimation option to estimate missing parameters. These capabilities (regression and estimation) are not available in the Properties environment of HYSYS. Aspen Properties can be selected directly in HYSYS or a new Properties file can be created and then imported into HYSYS.
Aspen Properties allows the user to specify more than one set of BIP being this, especially important when working with activity coefficient models because these property methods strongly depend on the temperature, so the user can create different sets of parameters at different range of temperatures. Furthermore, it allows the user to specify supercritical components such as CO2 or N2 as Henry components, so the binary interaction parameters will use the Henry’s law to determine the solubility of the supercritical components respect to the rest of the components of the system.
In the Properties example attached, Example_MEG_Water_HC.aprbkp, the Estimation option has been used to estimate the BIP parameters for the system CO2/Butane and MEG/Butane. Then, this file was imported into HYSYS in the Fluid Package folder. Please refer to theSolution ID 125517: How can I import Aspen Properties / Aspen Plus files into HYSYS?
In the HYSYS file, Example_MEG_Water_HC.hsc, a simple separator has been used to show the results obtained and the separation of the supercritical components, water and MEG is consistent with the results obtained in HYSYS.
If we consider the same system at high pressure, then an Equation of State such as Peng-Robinson should be used. In order to solve the issue with the missing binary interaction parameters, the user has two options: to provide the data directly in HYSYS or use Aspen Properties to provide the missing information and then import the file into HYSYS. The attached properties example can be used as reference.
Keywords: MEG, Property Package, Low pressure system, High pressure system
References: None |
Problem Statement: How does one select which streams are displayed in each Workbook tab? | Solution: To hide a stream:
1. Open up the Workbook and go to the tab of interest.
2. Right-click on the column pertaining to the desired stream and select Hide.
Alternatively:
1. Open up the Workbook and right click on the tab of interest.
2. Select the Order/Hide/Reveal menu option.
3. In the ensuing Order/Hide/Reveal Objects window, the list on the left shows the streams that are currently being displayed on the Workbook tab. To hide any of the streams in that list, highlight the stream name(s) and press the Hide button.
4. If there are any hidden streams (i.e. listed in the column on the right) that you wish to show, highlight the desired stream name(s) and press the Reveal button.
5. Click OK when you're finished.
Keywords: workbook, hide, streams, display, show, reveal
References: None |
Problem Statement: How to resolve Unable to load odbcji32.dll when trying to run interactive report | Solution: 1. Uninstall Microsoft Access Database Engine
On Windows 10 go to Settings > System > Apps & Features and search for access ...
Uninstall all versions of Microsoft Access Database Engine from your system.
On other systems use Uninstall or change Program or Repair or Remove Programs
Uninstall all versions of Microsoft Access Database Engine from your system.
2. Download and Re-install Microsoft Access Database Engine
§ Download the latest version of Microsoft Access Database Engine (2010) here:
http://www.microsoft.com/en-us/download/details.aspx?id=13255
Important: download the AccessDatabaseEngine.exe (not the _x64 version!)
§ Install the ODBC driver and retry.
If you still get the error Unable to load odbcji32.dll:
There are also known compatibility issues between 32bit ODBC drivers and 64bit versions of Microsoft Office.
It is recommended to install the 32bit version of Microsoft Office (instead of the 64bit version).
Also see related KB#146916.
Keywords: ODBC driver, odbcji32, ACCE, interactive report error, Microsoft Access installation, MS Office, Microsoft Access Database Engine 2010
References: None |
Problem Statement: How to set up a level controller on the shell side of a heat exchanger? | Solution: This is a workaround, and the the required steps are the following:
+ Add a spreadsheet to your simulation.
+Drag and drop the shell houldup liquid volume, from Dynamics tab, Holdup page to one cell in the spreadsheet.
+ Drag and drop the shell volume from Dynamics tab, Model page to another cell in the spreadsheet.
+ Include in the spreadsheet a formula to divide the holdup liquid volume by the shell volume and multiply the result by 100. This is not exactly the height level in the heat exchanger but it is a start, if level height is needed, an equation to calculate the level of liquid inside a horizontal cylinder is needed
+ Connect the Level Controller to the Spreadsheet as process variable and to the desired manipulated variable.
An example is attached to illustrate the results of the above implementation.
Keywords: Heat exchanger, shell side, level controller
References: None |
Problem Statement: How can I specify the Actuator parameters (rate, time constant, etc..) ? | Solution: These options appear on the Dynamics Tab, Actuator Page of the valve. However, you must have the HYSYS.Plant+ license enabled in order to modify these parameters. To enable the HYSYS.Plant+ license, go to the Options tab of the Integrator and select Use HYSYS.Plant+. The actuator parameters on the valve will now be shown in blue instead of black.
Keywords: Actuator, Valve
References: None |
Problem Statement: Can Aspen HYSYS be setup as a server application? | Solution: Yes, Aspen HYSYS can be setup as a server application but within certain constraints (as shown in the attached ApplicationServer.doc document).
As of Aspen HYSYS 2.4, we stopped officially supporting Aspen HYSYS installed on a network server (for all operating systems). The application was not developed nor intended to be run as a server application and and so technical support for these types of installations is very limited.
Having said that, it's known that Aspen HYSYS can be installed onto a server. The suggestions on how to set this up can be found in the Aspen HYSYS Get Started manual, in section 1.4.1 or in the attached document.
Further to the instructions outlined in the Get Started manual and the attached document, the following suggestions are strongly recommended:
* Have each user change their Aspen HYSYS preferences to look for the PAK, CASES and USER folders on the client's home drive.
* Copy the HYSYS.prf file from the server to the local client machine (e.g. C:\Temp\HYSYS.prf) and have the end users load up that HYSYS.prf (that contains their preferences) whenever they run Aspen HYSYS.
* Client machines require MSXML Parser 4 to be installed as well. You can get this from the Microsoft website (http://support.microsoft.com/ and perform a search for XML Parser).
Keywords: application, server, install, installation, terminal server
References: None |
Problem Statement: How can I access the new Property Correlations in Aspen HYSYS 3.1+? | Solution: The .GetCorrelationValue method of the ProcessStream object can be used to access any stream property. It is the only way that the new stream properties added in HYSYS 3.1 (Dew point values, Wobbe Index etc.) can be accessed.
The .GetCorrelationValue method takes two parameters and returns a RealVariable:
Function GetCorrelationValue(sCorrelationName As String, [sCorrelationType As String]) As RealVariable
sCorrelationName - required. This is the name of the property as it appears on the Properties page of the stream or the Correlation Picker sCorrelationType - an optional type name. This is necessary only if the property is not one of the standard properties
For example if hyStream is a ProcessStream object for a material stream then
Dim hyStream As HYSYS.ProcessStream
Dim hyRV As HYSYS.RealVariable
'...
Set hyRV = hyStream.GetCorrelationValue(Cp/(Cp - R))
and
Set hyRV = hyStream.GetCorrelationValue(Cp/(Cp - R), Standard)
both work equally well, but to access a Gas property use
Set hyRV = hyStream.GetCorrelationValue(Water Dew Point, Gas)
Note here the [Gas] appended to the property name on the properties page of the stream has not been included.
It is not necessary to add the property to a stream before retrieving it via VBA.
The following HYSYS Macro Language Editor code illustrates several of the new properties available. This looks for a stream called Gas + H2O, sample case G-2.hsc has such a stream. Paste the section between the dashed lines into the HYSYS Macro Language Editor (Tools ? Macro Language Editor)
Sub Main()
Dim hyApp As HYSYS.Application
Dim hyCase As HYSYS.SimulationCase
Dim hyStream As HYSYS.ProcessStream
Dim hyRV As HYSYS.RealVariable
'Link to HYSYS Objects
Set hyCase = ActiveCase
'For VBA in Excel
'Set hyApp = GetObject(, HYSYS.Application) 'Set hyCase = hyApp.ActiveDocument
Set hyStream = hyCase.Flowsheet.MaterialStreams.Item(Gas + H2O)
'Standard Properties
Keywords: None
References: None |
Problem Statement: In an extension unit operation using the .Calculate method on the .ComponentMolarFraction property of a ProcessStream Realvariable will not work unless the array of values passed has been normalised. This was not the case in HYSYS versions prior to 3.0.1 | Solution: Normalise the array that is being passed. The code snippet below illustrates this.
Dim Comps As Variant
Dim hyProdStream As HYSYS.ProcessStream
Dim i As Integer
Dim Total As Integer
'...
'Get an array with which to fill with values
Comps = hyProdStream.ComponentMolarFraction.GetValues()
'Put some dummy values in
Total = 0
For i = 0 To hyProdStream.FluidPackage.Components.Count - 1
Comps(i) = i
Total = Total + Comps(i)
Next 'i
'Now normalise
For i = 0 To hyProdStream.FluidPackage.Components.Count - 1
Comps(i) = Comps(i) / Total
Next 'i
'Set the values back
hyStream.ComponentMolarFraction.Calculate Comps,
Keywords: OLE Automation Extension .Calculate .ComponentMolarFraction
References: None |
Problem Statement: Do Bpcurves, GasProps, and Strmcopy extensions work with Aspen HYSYS V7.3 in Windows 7 64-bit environment? | Solution: Aspen HYSYS V7.3 is supported in Windows 7 64 bit machine, extensions should also work correctly. Aspen HYSYS is incompatible with Microsoft Office 64-bit.
Keywords: Windows 7, 64 bit, HYSYS V7.3
References: None |
Problem Statement: Is it possible to model a solid equilibrium in Aspen HYSYS? | Solution: Aspen HYSYS does not have the capability to predict the phase crystallization and there is not solid phase equilibrium data or methods inside of HYSYS that predict the behavior of a solid phase in the presence of other phases. This is why there are no solid with liquid, or gas or both equilibrium calculations.
If you are trying to model such a process, the recommendation is to use Aspen Plus on the Engineering Suite. The user will need to define two components for the substance that freezes. One will be for the solid and the other for the vapor-liquid. You can model the freezing either using a Chemistry reaction or using an RGibbs block, for more information please refer toSolution 3222.
Keywords: Solid equilibrium
References: None |
Problem Statement: How is the viscosity calculation made in the blend tab on the oil manager? | Solution: During blending, Aspen HYSYS internally combines all of the individual assay curves (TBP vs. weight percentage) and produces a single composite TBP curve. From this curve, Aspen HYSYS defines the hypocomponents and estimate their parameters such as Tc, Pc, MW, Accentricity, etc. The liquid viscosity coefficients A and B depend on these parameters and are calculated from one of the following models:
1. modification of the NBS method (Ely and Hanley)
2. Twu's model
3. or a modification of the Letsou-Stiel correlation.
Aspen HYSYS selects the appropriate model using the following criteria:
A? For non-Hydrocarbon or NBP < 270 K, Letsou Stiel is used
A? for Hydrocarbon and NBP < 335 K, NBS viscosity is used
A? all other cases, Twu is used.
For more information please refer to Aspen Simulation Basis, pages 3-22 and A-66, which you can download it completely from the followingSolution131895
Keywords: Viscosity calculation, blending, oil manager
References: None |
Problem Statement: Why does Aspen HYSYS (or any application) crash? | Solution: There are three general reasons why Aspen HYSYS (or any application) will crash.
1. Program bug.
2. Corrupt file.
3. Conflict with operating environment.
The user of the application must perform some basic diagnostic work to determine what the cause is of the crash which they are experiencing. When reporting the problem, it is imperative that the version (and Build) number are relayed (use Help...About HYSYS to check this information).
1. A program bug is a REPEATABLE sequence of events (keystrokes, mouse-clicks, etc.) which will cause a problem (either program crash or other undesirable result). As an example, during the Beta testing for the HYSYS.Process release in early 1999 a problem was found with Build 3105. It was determined that the following sequence of events would cause the application to crash.
- With the workbook open, choose Workbook...Setup...Add.
- Leave the New Object Type window open while the new Autosave function saves the current case to a temp file.
Once this particular REPEATABLE sequence of events was documented, it was corrected by the HYSYS development team. The critical thing here is that the application user recognized the sequence of events which led to the crash and was able to relay that information to us. Without that information, the bug cannot be fixed.
2. A corrupt case can cause Aspen HYSYS to crash. While it is almost impossible to know what caused the case to become corrupted (and in most cases it is impossible to correct), it is usually fairly easy to determine if the application crash is being caused by a corrupt case. If a certain sequence of events causes Aspen HYSYS to crash when running a particular case, but not when running another case, then in all likelihood the case has been corrupted. Experimenting with the sample cases shipped with Aspen HYSYS is another good test. If Aspen HYSYS crashes during the same sequence of events on several files, consider the possibility that the cases were derived from a common source file and BOTH contain the problem.
3. The first two causes listed above account for the vast majority of Aspen HYSYS application crashes. The third cause is much more difficult to diagnose and will require the cooperation of the user's IT (computer) support personnel to solve. The problem could range from a problem with a memory chip to a conflict with another piece of software installed on the computer.
Keywords: Crash, Corrupt, defect, bug
References: None |
Problem Statement: What is the difference between Straight and Relief side weir types? | Solution: There are two types of weirs available in Aspen HYSYS: straight and relief.
A relief weir lengthens the side weir without increasing the downcomer area. The relief weir sweeps back, then across the tray, enclosing some active area.
A straight weir follows the edge of the downcomer.
A relief weir is used for high liquid loads or where a low pressure drop is required, while straight weirs are used for normal service. Aspen HYSYS uses a straight weir as the default.
For more information on the Tray Sizing Utility please refer to the Aspen HYSYS Operations Guide.
Keywords: straight, relief, weir, tray sizing
References: None |
Problem Statement: In real separator ProSeparator correlations, what is the meaning of dm in Rossin Rammler Parameters? | Solution: The term dm is the mean particle size and it is related to d95, which is 95% of droplets are smaller than this diameter for the specified dispersion.
Keywords: Real separator, ProSeparator, Rossin Rammler Parameters
References: None |
Problem Statement: How do I convert the heat curve in the Heat Exchanger and Heater operations from a molar basis to a mass basis? | Solution: In order to generate a heat curve on a mass basis, you will need to create a Property Table utility according to the instructions provided below:
1. Select Tools | Utilities from the main menu and add a Property Table utility.
2. Choose the inlet stream to the Heater or the Heat Exchanger in the Property Table connections page.
3. For the 1st Independent variable, select Pressure and choose a range that encompasses the inlet and outlet conditions of the heater or heat exchanger.
3. For the 2nd Independent variable, select Temperature and again choose a range that encompasses the inlet and outlet conditions of the heater or heat exchanger.
4. Switch to the Dep. Prop. page and select Mass Enthalpy as the Dependent Property.
5. Press the Calculate button at the bottom of the window.
6. View the Results as a Table or Plot on the Performance tab.
Keywords: heat curve, property table, mass enthalpy, heater, heat exchanger, units, conversion
References: None |
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