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Problem Statement: What is the best exchanger configuration for tubeside, vertical condensation? | Solution: There are 2 choices for condensation inside vertical tubes:
1. The normal condenser has the vapor entering at the top with downward flow of both the vapor and condensate.
2. The knock-back condenser is the alternative. With a knockback condenser the vapor enters from the bottom. As the condensate forms on the wall, it drains down flowing counter to the hot vapor stream. The condensate can't get subcooled. Furthermore, if the vapor velocity is too high, it can result in the flooding of the tubes with liquid unable to flow downward. The knockback condenser is used when it is important to limit sub-cooling of the condensate. It will typically result in a larger design due to limits placed on the maximum velocity to avoid flooding.
Keywords: Hetran, Tasc+, condenser, knockback, knock back, vertical, heat exchanger
References: None |
Problem Statement: Excess demand (orders) and shipments during the present time period in DM is consuming the next time period's forecast. | Solution: Adjust the Demand Plan Option switches in the APPDATA table switches:
(DMPLNET_LABS) Net Abs Left - # of Net Abs Pds to left [0-n] - Limits the number of prior months in which excess orders can be netted out of the forecast. Set to zero for no netting of the forecast.
(DMPLNET_LREL) Net Rel Left - # of Net Pds to the left [0-n] - Nets excess orders out of the forecast in the specified number of past netting periods. Set to zero for no netting of the forecast.
(DMPLNET_RABS) Net Abs Right - # of Net Abs Pds to right [0-n] - Allows excess orders to be consumed from X number of future months of the forecast. Set to zero for no netting of the forecast.
(DMPLNET_RREL) Net Rel Right - # of Net Pds to the right [0-n] - Nets excess orders out of the forecast in the specified number of future netting periods. Set to zero for no netting of the forecast.
These parameters determine how far back in time and how far forward in time you will allow orders to consume forecast in the netting process.
If you were using weekly periods to net your monthly forecast you could limit the netting to 5 weeks (REL) and 4 months (ABS) (backward and forward in time), or by setting all switches to zero (0) you allow no netting past or future.
Keywords: sales order netting
References: None |
Problem Statement: You have a CDM case you need to work on but are unable to view any menus upon opening the model. Why is this? | Solution: One of the reasons for this message to occur is when table $TCASES (defines the fully qualified file name of each remote case) does not point to the correct paths or remote cases of the Shared Libraries.
In order to resolve this problem, load your CAPS case file, open any set or tables and open the Attributes window.
In the Load Case parameter, verify that the remote Shared Libaries cases in the list box match the cases indicated in $TCASES table (FIG 3).
Also verify that $TCASES table is pointing to the correct Shared Libraries cases location.
Apply changes to the table.
Save the case.
Reload the case again and the case should load OK this time.
Keywords: $TCASES
Demand Manager
References: None |
Problem Statement: How to resolve the following error message while opening Exchanger Design and Rating interface? | Solution: EDR temporarily stores all the recent files for quick accessibility. When this memory reaches a limit, EDR informs the same to user with the above dialog box. Clicking on Yes, clears the temporary memory without removing the actual files from the location. While clicking on No, still allows the user to start the application. It is recommended to clean the cached memory as and when possible.
Keywords: BJAC error message, EDR.
References: None |
Problem Statement: When the data was published from any application with a specific publisher topic in order for the Aspen Reporting Framework (ARF) to start listening to that topic and update the ARF database the same topic name called subscriber topic needs to be added within ARF. This | Solution: outlines how to add these Subscriber topics from the ARF GUI.Solution
Go to Start-->Programs-->Aspentech-->Aspentech Infrastructure-->Aspen Reporting Framework which opens up the ARF Administrator window.
? Navigate to the Configure Operations tab in the ARF Administrator and click on Add Button near the EIF Subscription List box. This opens up the 'Add Subscription' dialog box and type the Subscription Name topic that needs to be specified. Click OK and see the subscriber topic entered is displayed in the ARF GUI and then click on save button to save the configuration.
Multiple Subscriber topics can be added within the ARF GUI using the same procedure mentioned above.
Note: Please note that adding or deleting any Subscription topics can be done only when the ARF Service is stopped/not running.
Keywords: Subscriber Topic
ARF
References: None |
Problem Statement: What is the definition of Predictor / Price and when is it used? | Solution: A predictor may help to explain the behavior of the series being forecast.
Some examples of predictor are
? Weather
Crude Prices
Government metrics e.g. Durable goods index, CPI ?
Working days in a month
Keywords: None
References: None |
Problem Statement: When opening an Exchanger Design and Rating (*.EDR) file, the program crashes. | Solution: There have been a few occasions when opening an EDR file the program crashes. The crash generally seems to occur just after the program has reported connecting to local server for Aspen Properties.
The workaround is to open the file in a text editor, like NotePad, for example and save. It is suspected that when input files are emailed they can sometimes become corrupted. If this is the case, then the files could be zipped.
Keywords: run-time error, run time error, automation error, server, exception
References: None |
Problem Statement: How can I model heat exchangers with a different number of tubes in each pass? | Solution: From Aspen Shell & Tube Exchanger V7.20 onwards, it is possible to specify passes with a different number of tubes as given inSolution #128490.
In older versions of Aspen Shell & Tube Exchanger it is only possible to model exchangers with the same number of tubes in each pass. On some occasions users wish to model exchangers with a different number of tubes in some passes (for example a tube pass for subcooling condensate in a horizontal tubeside condenser may be designed with a smaller tube to maintain a high velocity). The following workaround is intended to provide an approximateSolution for a limited set of process conditions.
It will work best when the mean temperature difference in each tube pass can be approximated by the log mean temperature difference, the tube side coefficient in each pass is uniform, and the shellside heat transfer coefficient is either constant or significantly greater than the tube side heat transfer coefficient.
Note that this procedure is not necessary if there is only a small difference in the tube counts per pass.
The following procedure is a Checking (Rating) calculation that generates the required Surface Area, and it applies to a unit with two tube passes.
1. Use Aspen Shell and Tube Exchanger in Checking/Rating mode to model the unit with the actual shell diameter and total number of tubes (with the same number of tubes in each pass). Note the shellside average heat transfer coefficient and pressure drop.
2. Use to results to form a guess of the tubeside interpass temperature t* with the actual tube count in each pass. Calculate the implied individual pass heat loads Q1 and Q2 from t* and the tubeside flowrate and temperature/enthalpy curve.
3. Calculate the LMTD for each tube pass using the terminal temperatures for each pass and the shellside inlet and outlet temperatures
4. Calculate the mean temperature difference MTD for the unit from
1/MTD = [(Q1/(LMTD1) + Q2/(LMTD2))/(Q1+Q2)
5. In two separate Shell and Tube Exchanger runs, model two smaller shell diameter exchangers, one for each pass (with the correct number of tubes for each pass). Use the constant shellside coefficient calculated in 1 above. Note that if the shellside is two phase you need to input a constant coefficient for the single phase liquid, single phase gas and two phase coefficients on the Program Options...Thermal Analysis tab. Note the overall mean heat transfer coefficients Um1 and Um2 and pressure drops calculated.
6. Calculate the heat load Q1 for the first tube pass from
Q1 = Um1*LMTD1*A1
where A1 is the surface area of the first tube pass
7. Use the tubeside temperature enthalpy curve to calculate the corresponding outlet temperature t1* from the first tube pass. Compare t1* with the initial guess of t*. If they are different (to within a reasonable tolerance), adjust the estimate of t* and repeat steps 2 to 7 until t1* and t* converge
8. Calculate a mean overall heat transfer coefficient Um for the actual exchanger from
Um = (Um1*A1 +Um2*A2)/(A1 + A2)
where A1 and A2 are the surface areas of each tube pass
9. Calculate the total surface area A required from
A = (Q1 + Q2)/(Um*MTD)
10. Use the information from the runs in step 5 to calculate the tubeside pressure drop.
A similar procedure is possible if there are three or more tube passes, but iteration will be required on each interpass temperature and the calculation may be time-consuming.
Keywords: tubes, passes, number, variable
References: None |
Problem Statement: In APC Builder, the master model can be updated by various cases. However, only one trial (TTSS) is selected to update the master model. If the master trial is changed, there is no way to know which trials of the case the curve comes from. | Solution: The master model in APC Builder can comprise of response curves from several cases. If you want to know which case is used to update the curve in the master model, go to the master model node and select on that response curve. The cases that have the response curves will be highlighted; Yellow highlight is used for cases that have the Dep-Ind pair in their structure and Green highlight is used for the case that was used to update the master model (screenshot below).
For each cases, the only trail that can update the master model is the master trial. The master trial selection can be changed at any time so it is a best practice to update the master model when the master trial of the case is changed to ensure the correct curve is copied to the master trial.
Keywords: APC Builder
Update response curve
Master trial
References: None |
Problem Statement: Is Aspen Collaborative Demand Manager supported in a virtual environment? | Solution: The following table illustrates Aspen Collaborative Demand Manager (listed as Aspen Chemical Supply Chain) and the supported virtualization technologies.
Virtualization Technology
Aspen Chemical Supply Chain
VMware ESX Server
Yes
Microsoft Hyper-V
Yes
Citrix Presentation Server
Yes
Microsoft Terminal Server
Yes
Microsoft Application Virtualization
No
Keywords: None
References: None |
Problem Statement: I am unable to pass data between Aspen Tasc+ and Aspen HYSYS. | Solution: 1. Go to START | Program Files | .... | Aspen HTFS+ 2006(or 2006.5) | Version Control Utility and select version 20 for 2006 version or 21 for 2006.5 version. Next, go to START | Program Files | ..... | Aspen HYSYS 2006 (or 2006.5) | Restore File Associations.
If the above procedure does not solve the problem, please perform a Registry Cleanup as described below:
2. Go to C:\Program Files\AspenTech\Aspen HTFS+ 2006\XEQ and double click on BjacRegClean.exe. Click OK to any message windows that appear, then click on Search Registry. Wait until the search is complete, then click on Clean Up.
Keywords: Tasc+, htfs+, import, export, import, HYSYS
References: None |
Problem Statement: Is it possible to make sure the outlet stream is at saturated condition, either a saturated liquid or saturated vapor? | Solution: The saturation temperature may not be known because exact pressure drop has not been determined. In order to specify saturated conditions, specify a vapor mass fraction equal to 1 (for saturated vapor) or 0 (for saturated liquid) and keep temperature empty. You must keep the flowrate field of the desired stream empty if you want Aspen Tasc+ to calculate it.
Keywords: Saturated, flowrate, adjust flowrate,
References: None |
Problem Statement: Why are the nozzle sizes in TEMA are different than my specifications? | Solution: The nozzle size in TEMA can be different that the specifications when whenever there are incomplete nozzle size specifications.
Entering only the nominal diameter specification is not enough. You have to specify actual OD and ID or wall thickness. If you enter only a standard nominal diameter, Tasc+ uses a default OD, ID and wall thickness. It is possible to can change these values. If you specify a non-standard nominal diameter, Tasc+ keeps OD, ID and wall thickness empty. If you run keeping them empty, Tasc+ will ignore your nominal diameter specification.
Keywords: Different diameter, diameter, nominal diameter, different, change, nozzle, nozzle size
References: None |
Problem Statement: When a user trying to log into the Collaborative Forecasting application, the server returns the following unexpected condition error message:
Note: Administrator - can login and add a new user to Aspen Collaborative Forecasting. | Solution: This error can also appear when the AeBRSSLM.dll DLL is missing in the CF domain folder. You can get it from the attachment to this document: put it into the domain folder and then restart the server.
Keywords: Collaborative Forecasting
Encountered
Unexpected condition
Fulfilling
Request
Server error
CF login
References: None |
Problem Statement: In Aspen Properties V7.2 and newer versions, new steam table data such as ?IAPWS-1995? was introduced. Since Aspen Properties can be used inside of Aspen Exchanger Design and Rating (EDR) when generating stream physical properties, it is possible to use this steam table in EDR now for physical property generation. This | Solution: describes how to use and its validity range/circumstances.
Solution
Firstly, users need to make sure Aspen Properties V7.2 or newer is installed and registered properly, whereSolution 126231 can be consulted.
After Aspen Properties is installed and associated with EDR properly, go to Input | Property Data |Hot/Cold Stream Compositions | Property Methods tab, where from the drop-down list for Aspen property method users can select ?IAPWS-95?.
Please note only when Aspen Properties V7.2 and a newer version are used within EDR will this set of steam table data be available.
Afterwards, users can go to Input | Property Data |Hot/Cold Stream Properties | Properties tab to ?Get Properties?.
Please note that steam tables, including IAPWS-95 and earlier editions, should only be used for pure water systems, under certain operating conditions. For example, IAPWS-95 covers a validity range for temperatures from the melting line (lowest temperature 251.2 K at 209.9 MPa) to 1273 K and pressure up to 1000 MPa. In the stable fluid region, IAPWS-95 formulation can be extrapolated beyond these limits, to some extent, still with a fairly good accuracy level.
Users should use the steam table property packages for pure water systems only, not adding any additional components to create a mixture.
Keywords: IAPWS-1995, IAPWS-95, Steam Table, Aspen Properties, V7.2, V7.3
References: None |
Problem Statement: When I run a Shell & Tube Exchanger case, the calculation stops and gives error message input Error 1122 ? The data input for Number of tube passes, 1 is beyond the permitted range, from 2 to 16. Where does this error come from and how can it be resolved? | Solution: This error is due to the user specifying the numbers of tube pass as 1 combined with a U-tube rear head type. These inputs can be found either on the Input | Exchanger Geometry | Geometry Summary | Geometry tab, Input | Exchanger Geometry | Shell/Heads/Flanges/Tubesheets/Shell/Heads tab or the Input | Exchanger Geometry | Bundle layout | Layout Parameters tab.
A U-bend rear head type makes it compulsory to have the tubeside inlet and outlet nozzles located on the front head of the exchanger, which means the number of tube pass must be at least 2 passes or a multiple ( e.g., 4,6,8?). Setting an odd number of tube passes will result in an input error 1124, as described inSolution 130063.
Keywords: Error 1122, Number of tube passes 1, beyond the permitted range, U rear head type, U bend
References: None |
Problem Statement: If deresonating baffles are used in designing a heat exchanger, how is an external user informed of the deresonating baffles? | Solution: As of now, Aspen Shell & Tube Exchanger does not display deresonating baffles in TEMA sheet or setting plan.
The user can add information on deresonating baffles in the remarks column under Problem Definition-> Heading/Remarks-> TEMA Specifications Sheet.
Keywords: Deresonating baffle, EDR, TEMA sheet
References: None |
Problem Statement: When importing process and property data from Aspen HYSYS to Aspen Tasc+, certain streams may carry additional information that result in warning messages being generated in Aspen Tasc+. This is of particular concern for streams in Aspen HYSYS leaving a 3-phase separator. | Solution: In Aspen HYSYS, if a vapor product stream from a 3-phase separator is attached to a heat exchanger and you import the process and property data from that heat exchanger into Aspen Tasc+, you will ultimately transfer the properties of all three phases present in that vapor stream (the existing vapor phase, and the incipient liquid and aqueous phase).
To avoid this problem, add another unit operation in Aspen HYSYS between the target stream (i.e. the vapor stream from the 3-phase separator) and the heat exchanger (i.e. insert a cooler or heater with zero pressure drop and zero duty). The product stream from this additional unit operation contains only single phase information and you will avoid any warning messages resulting from the above issue.
Keywords: Tasc+, HYSYS, 3-phase separator, properties
References: None |
Problem Statement: How do I set token limit user alerts through the Aspen Licensing Dashboard? | Solution: This KB article explains how to set user alerts through the Aspen Licensing Dashboard. For information regarding installation and configuration of the Aspen Licensing Dashboard, please see KB 146044.
Setting Alerts
You can use the Set Alerts button on the Aspen Licensing Dashboard screen to enable email or event log notification.
You can set the Aspen Licensing Dashboard to send you emails when the following occur:
• When SLM License Manager service has stopped.
• When a license is due to expire.
• When SLM_Pool license is close to the limit (10%, 5%, and 1%).
License Alerts Displayed
• Usage denial durations appear for 6 months, 3 months, 1 month, and 1
week. You can view the user and the license that they were attempting to
use.
• License alerts notify you if licenses are no longer being granted due to loss
of network connection to the license server or if the license server service
has stopped responding.
• License alerts show pending expirations of licenses. You can view the date
of the license that will expire the earliest, as well as all of the licenses and
their expiration dates for each server.
Keywords: Token limit
User alerts
User alarms
Aspen Licensing Dashboard
References: None |
Problem Statement: Aspen Supply Chain Connect users are using Informatica 8.6.0 to get material on orders data from SAP and put them into Demand Manager 2006.6. Is Informatica Powercenter 8.6.X is going out of standard support? | Solution: Informatica PowerCenter 8.6.X end of standard support will be on December 2011. Informatica yet to announce End of Extended Support for 8.6.X.
Keywords: Informatica PowerCenter 8.6.X
End of support
End-of-Life
Informatica products
References: None |
Problem Statement: Fouling factors reported in TEMA sheet do not match the fouling factors specified in the process data sheet. How does Aspen Tasc+ calculate the fouling factors reported in the TEMA sheet? | Solution: Fouling factors found on the Input | Process Data page are based on local area (i.e. tube ID for tube side, finned area for finned tubes).
Output fouling factors and heat transfer coefficients are calculated relative to the standard reference area (based on the tube OD).
Output tube side fouling (based on tube O.D) = Specified tube side fouling * (Tube OD / Tube ID).
Shell side fouling is based on Area (using the tube OD including fin area).
For plain tubes, calculated shell side fouling = shell side fouling specified on the Process data page.
For finned tubes, calculated shell side fouling = Shell side fouling specified * Effective surface area / Gross surface area (i.e. bare tube area based on OD + finned area per shell).
Keywords: fouling, factor, TEMA, sheet, area
References: None |
Problem Statement: How do I use the validation routine when using CUSFMT or CUSSQL import options when importing material master? | Solution: To get the processed records and accepted records reflected correctly, please put APPEND RECCNT NEXT NULL ACTUAL at the very beginning of the FMTDATA statements (PROMAST).
To get detail information in validation log, for CUSSQL method because the DM tool can?t recognize the custom validation logic in the FMTDATA statements, it is not standard functionality in DM tool. It requires some custom code embedded in the FMTDATA statements to pick up those dropped entries and then write those entries to the validation log.
Keywords: None
References: None |
Problem Statement: How do I update McAfee protection rules to enable Email option in Sharepoint?
Several features of Aspen Search use SharePoint including: Email, Alerts.
In order to be able to Email a search result to a colleague, or trigger an alert whenever an item is changed, email must be correctly configured on the SharePoint server where Aspen Search is installed. Sometimes McAfee protection rules block emails being sent. This | Solution: addresses this problem.
Solution
1. Open McAfee VirusScan Console
2. Select Access Protection
3. Click the Task menu and select Properties, and the Access Protection Properties window comes up.
4. On the Access Protection Tab, select Anti-virus Standard Protection category
5. Select Prevent mass mailing worms from sending mail rule and verify both Block and Report options are checked for the rule.
6. Click the Edit button and the Rule Details dialog comes up.
7. Add the process w3wp.exe to the Processes to exclude field box.
8. Click OK to close the Rule Details dialog.
9. Click Apply to apply the new rule and click OK to close the Access Protection Properties window.
10. Close the McAfee VirusScan Console.
Keywords: enable email option
References: None |
Problem Statement: After running the file, the Input Error 1198 appears in Results | Results Summary | Warnings & Messages.
How can I get rid of this error? | Solution: Incorrect shell nozzle locations can lead to flooding in condenser shells. As the message states, the shell inlet nozzle has to be at the top and the shell outlet nozzle must be at the bottom to prevent the shell flooding during the condensation.
To modify the nozzle location, you must go to Exchanger Geometry | Nozzles | Shell Side Nozzles and select the correct orientation for the inlet and outlet nozzles.
Keywords: Error 1198, Shell flooding, nozzle location.
References: None |
Problem Statement: How to changed default unit set in EDR? | Solution: To change default unit set in EDR, please go to File and then click on Options page to open Program settings window.
In Program settings window go to General page and Click the pull-down arrow next to the units of measure option to change default unit set and Click OK to save the change.
Please find below screenshot for your reference.
Keywords: Default Unit set.
References: None |
Problem Statement: How does Optimal Forecast Method handles set DMPST and forecasting parameter ERRCALC in Aspen Collaborative Demand Manager? | Solution: DMPST (Past periods set) contains 24 periods and forecasting parameter ERRCALC (Number of past periods to be used to compare forecast and shipments - Default value is 6) is set to 6.
In this specific example, does the optimal forecast method selection process ignore the first 18 periods ?
No. It fits each method using the first 18 periods and measures the error over the remaining 6 periods; then it fits using the first 19 periods and measures the error over the last 5 periods. It will lastly fit using the first 23 periods and measure the error in the final period. After adding up all the errors, it selects the best fit and fits that method to all 24 observations.
Keywords: None
References: None |
Problem Statement: How do you save the Tasc+ TEMA Sheet in an Adobe Acrobat PDF format? | Solution: Tasc+ does not have an option to directly create PDF files for the TEMA datasheet or any of the other HTFS+ results forms. If you have the Adobe Acrobat PDF Writer software (or one of the many inexpensive or free PDF writer work-alikes), you can PRINT the TEMA data sheet and choose the PDF print driver from the list of printers.
The other option is to use the FILE | EXPORT option to send the Tasc+ results to either an MS Excel spreadsheet or a MS Word document.
To export TEMA sheet into Excel format go to 'File' on the main menu and select 'Export to'. When prompted, choose the option of Excel or Word and if asked, choose option of a default template or any existing Template in the ..\Program Files\AspenTech\Aspen HTFS+ 2006\Dat\Template folder
If you have problems printing the TEMA sheet (such as overlapping data in the printed form) you can perform the above steps to EXPORT and then print the TEMA sheet from the exported file.
Keywords: TEMA Sheet, export, Print, Microsoft Excel, Microsoft Word, Adobe Acrobat, PDF
References: None |
Problem Statement: In Exchanger Design & Rating (EDR) V7.3.1, you can enter the percentage of the Impingement plate perforated area for values between 1 to 100. Values less than 1% are taken as a fraction. | Solution: In Aspen Shell &Tube Exchanger, Input | Exchanger Geometry | Nozzles | Impingement | Impingement plate perforated area, the % value is not applicable for whole range (0-100%). For values lees than 1% Shell & Tube handles it as a fraction in order to be able to import files from V7.30 or older without any corrections required (e.g 0.3 in V7.30, when read into V7.3.1 or newer becomes 30%).
Keywords: Impingement plate perforated area
References: None |
Problem Statement: 在Aspen Properties (物性程序) V7.2和以上版本里，一个新的蒸汽表数据'IAPWS-1995'被引入了。既然Aspen Properties (物性程序)可以在EDR (换热器)程序里面使用，现在在EDR (换热器)程序里面这个新的蒸汽表也能被用户使用了。此解决方案详细讲述怎样在EDR里使用它，以及它的可用区间。 | Solution: 首先，用户要确保Aspen Properties V7.2或者更高版本已经正确的被安装和注册。关于此详细信息可以在解决方案126231里找到。
在确保Aspen Properties V7.2或者更高版本已经正确的被安装和注册及连接到EDR后，用户应该到Input | Property Data |Hot/Cold Stream Compositions | Property Methods 界面，从物性方法的下拉菜单里选择'IAPWS-95'。
请注意，只有在Aspen Properties V7.2或更高版本与EDR连接使用时，此新的蒸汽表才会可用。
然后，用户应该到Input | Property Data |Hot/Cold Stream Properties | Properties 界面来生成物性数据。
请注意，蒸汽表（包括此新蒸汽表IAPWS-95 和之前的旧版本的蒸汽表）只能用于纯物质 - 水（或蒸汽），并且只能在特定的操作条件下。例如，IAPWS-95的可用温度区间是从融点（在209.9 MPa压力下的251.2 K）到1273 K，压力最高可以到1000 MPa。在稳定流体范围内，, IAPWS-95方程甚至可以相当程度的被演推到这些范围以外，并仍保持相对较好的准确性。
用户应注意，不要用蒸汽表作用于非纯水的物流。
Keywords: IAPWS-1995, IAPWS-95, 蒸汽表，Aspen Properties （物性程序），V7.2, V7.3， 更高版本，CN -
References: None |
Problem Statement: Installing TASC 2004.2 after TASC+ 2004.2 was installed cause both software versions stop working. Now the following error appears:
Error: unable to load dynamic library zetasc | Solution: 1. Check the active version of Tasc+. Click on the Windows START button, then go to Programs | AspenTech | Aspen Engineering Suite | HTFS+ 2004.2 | Version Control Utility. Make sure the version control utility is pointing to the correct version (13.3), if not, please change the version:
2. Manually correct registry under:
HKEY_LOCAL_MACHINE/SOFTWARE/Aspentech/B-JAC/13.3/BJACWIN/BJAC_TOP
This should point to HTFS+ installation folder
3. If none of the above works, use the WINDOWS ADD/REMOVE programs utility to uninstall and reinstall HTFS+. The AspenTech uninstaller utility might not completely uninstall the TASC+ application.
Keywords: zetasc, tasc
tasc+
version
version control
References: None |
Problem Statement: General rules for avoiding instability (warning) in a thermosiphon. | Solution: General rules for avoiding instability (warning) in a thermosiphon:
1. Since instabilities are associated with two-phase effects, ensure that a significant fraction of the pressure drop around the loop occurs in the single phase region (i.e. inlet pipe network). It can be achieved by
placing valve in the inlet pipe. The inlet pressure loss can be increased by partly closing the valve.
decreasing diameter of inlet pipe etc.
2. Reduce the pressure loss at the exit from the boiler section as far as possible. It can be achieved by
- minimizing the outlet restriction from the channel.
- increasing pipe diameter.
- avoiding valves or any other form of outlet restrictions etc.
REFERENCES:
HTFS Handbook: TP7: Instabilities in Two-Phase Flow
HTFS Handbook: TM16: Stability Assessment of Boiling Two-Phase Systems
HTFS Design Report: DR1: Vertical Thermosiphon Reboilers
HTFS Design Report: DR17: Instabilities in Two-Phase Flow Systems
Please note: that the above HTFS handbooks are in HTFS website Research Network but can only be accessed by customers who have paid for it. Otherwise, they are proprietary to us and we can not send out any information from them.
Keywords: Thermosiphon, instability, warning.
References: None |
Problem Statement: Sometime when users open their *.EDR cases, they find the tree-menu on the left hand side of the diagram has disappeared. If they do not know how to restore it, it will be very inconvenient. | Solution: The reason why the tree-menu has disappeared is because the ''Hide Folder List'' button has been clicked down accidentally, as shown below.
This is for better view of information on certain folders. As soon as users want to move to other folders, they can restore the tree-menu by clicking up the ''Hide Folder List'' button.
Keywords: Hide folder list, tree-menu, disappear, restore.
References: None |
Problem Statement: When performing a search, the following error is displayed:
The attempted operation is prohibited because it exceeds the list view threshold enforced by the administrator. | Solution: The problem is occurring because the default SharePoint setting is to limit database operations to 5000.
The reSolution to this error is:
1. Login to the Aspen Search server machine as the installation administrator.
2. Open SharePoint 2010 Central Administration.
3. Go to Application Management > Manage Web Application and click on Aspen Search to select it.
4. In the Ribbon, click on General Settings drop-down and choose Resource Throttling.
5. In the List View Threshold, increase the value (by a factor of 2, for example) and click OK.
6. Try to replicate the error. If the error persists, increase the value again until the error goes away.
Keywords: SharePoint, search
References: None |
Problem Statement: How are diametric clearances defined? | Solution: Baffle OD to shell ID diametric clearance: twice the average distance between the baffle's edge (uncut portion) and the inside shell wall of the shell
Shell ID to Outer Tube Limit diametric clearance: twice the distance between the inside wall of the shell and the outside wall of the outmost tube
Keywords: diametric, clearance, definition
References: None |
Problem Statement: Why am I unable to publish or re-publish from Aspen Collaborative Demand Manager (CDM) to Aspen Collaborative Forecasting (CF)? Publish/republish does not complete. When I check CF the last republish date is in the past and the data in CF does not match DM.
Its possible that I can possibly see an error message with a comment similar to this one:
E0025:ROWSET ENTRY NOT FOUND IN SET OVERRIDS
SET: RCFPUB RULE: RCFPUB71 COND: ?COMMENT = CFSTCMT(DM28,COMMENT) | Solution: Check to see if the sets OVERRIDS and SOVERRID are in sync. The two sets must contain the same data in order to publish/republish from DM to CF. Delete the data in SOVERRID that is not in OVERRID and re-run republish.
Keywords: Publish
Re-publish
References: None |
Problem Statement: How do I configure Aspen Search when the test to confirm the connection to network share resources doesn't pass? | Solution: To identify the cause:
Verify the credentials for the SOLR search engine
Verify the LDAP configuration domain name and domain account credentials
To verify the SOLR search engine credentials:
1. Open Internet Explorer and enter the following URL:
http://<Aspen Search Server Name>:8080/solr/admin/
2. Enter the SOLR Configuration username and password from Row 8 in the Deployment Quick
Keywords:
References: If you are not able to gain access, check for the following issues:
Your Aspen Search server is not running, in which case you would receive an Invalid URL message. Verify that the server is accessible and that Apache Tomcat 7 service is running.
The entered SOLR configuration username or password might be incorrect. Refer to Chapter 12 of the installation guide for information on changing the password.
If you are able to gain access to the SOLR search engine, then the most likely cause of the test failure is the LDAP security configuration.
To verify the LDAP configuration domain name and domain account credentials:
1. On the Aspen Search server, find the solrconfig.xml file in the location where you installed the files. e.g.,
C:\Program Files\AspenTech\AspenSearch\Tomcat7.0.8\appdata\solr\conf
2. Open solrconfig.xml for editing. Search for the word enabled in the file; you might see something similar to the following:
searchComponent name=security class=com.aspentech.solr.security.AddSolrSecurity>
<str name=enabled>true</str>
3. Replace true with false.
4. Save the file. You have now disabled the LDAP security.
5. Go to C:\Windows\system32 and open Services.
6. Right click Apache Tomcat 7 and select Restart.
7. Open Aspen Search Configuration and click the Test button.
If the test is successful, verify the domain name in the AspenSearchSolrSecurity.xml file. Note: If you need to change the LDAP password, refer to Chapter 12 in the installation guide.
1. Open the file AspenSearchSolrSecurity.xml for editing. This file is located in the same folder as solrconfig.xml.
2. Find the line
<str name=domain>XYZ</str>
where XYZ should be your domain name.
3. If it is not your domain name, replace XYZ with your domain name.
4. Save the file.
After you save the file, re-enable the security by following these steps.
1. Open the solrconfig.xml file for editing.
2. Search for the word enabled in the file; you might see something similar to the following:
searchComponent name=security
class=com.aspentech.solr.security.AddSolrSecurity>
<str name=enabled>false</str>
3. Replace false with true.
4. Save the file.
5. Go to C:\Windows\system32 and open Services.
6. Right-click Apache Tomcat 7 and select Restart.
7. Open Aspen Search Configuration and click the Test button or run Aspen Search.
The security features are now re-enabled. |
Problem Statement: If your Aspen Search fails to process new or updated models, or services no longer work as expected, this might be the result of a password change on the Installation administrator?s account. If the Installation Administrators account has recently undergone a password update, follow these steps to resolve the issue. | Solution: If the Installation Administrators account has recently undergone a password update, follow these steps to resolve the issue:
Services
1. Open Services manager (Start | Administrative Tools | Services)
2. Right Mouse Click: Apache Tomcat 7 and select Properties
3. Select the Log On tab
4. Enter the new password in the Password: and Confirm password: fields, and click OK
5. Restart the Apache Tomcat 7 service
IIS
1. Open the IIS Manager (Start | Administrative Tools | Internet Information Services (IIS) Manager)
2. Select Application Pools.
3. Select the AppPool(Aspen Search)
4. Select Advanced Settings in the Actions column.
5. Find and click on Identity under Process Model and click the [?] button.
6. Click Set?
7. Specify the new user name and password.
8. Repeat steps 4-7 for all application pools with the Identity of the account who's password has changed
Open Pipeline
1. From Google Chrome, enter URL for OPenPipeline (this has changed in the new version of Aspen Search)
V7.3.1: http:// <server name>:8080/admin/view_jobs.jsp
V7.3.2: http://<server name>:8080/AspenCoreSearch/view_jobs.jsp
2. For each job you have create (file and tag):
a. Edit the job, and hit Next until you see the Configure Stages page
b. Next to FetchUri, click on (config)
c. Enter the new password in the Basic Auth Password: field
Keywords:
References: None |
Problem Statement: The user has an AKU shell, with steam inside the tubes and a boiling liquid on the shell side. Aspen Hetran assumes he wants the first pass (top half of the u tubes) to receive the hot steam (horizontal partition). In his heat exchanger, the partition is actually vertical, so the hot steam goes into the left side of the bundle, and exits on the right side of the bundle.
Does Aspen Hetran have a way to accommodate this alternate flow configuration? | Solution: It will not impact the thermal calculations. Steam will be condensing isothermally (no impact on the MTD). The film coefficient will also not be affected. The coefficient is also so high for steam that it has very little affect on the required surface area.
The only problem will be with the tubesheet layout drawing. The user can get around this problem with a note indicating to what angle the bundle has been rotated.
Aspen Tasc+ users can set the Orientation of U bends to be Horizontal or Vertical so that the user will not have the problem as in Aspen Hetran.
Keywords: None
References: None |
Problem Statement: I am upgrading a file in Simulation or Rating mode that has User specified properties in both vapor and liquid phase, from V8.4 to any newer version.
The results of the overall film coefficients do not match between versions, the key results as area ratio or outlet temperatures are inconsistent between versions.
Why are the results different between these versions? | Solution: This error can happen when values entered manually for Vapor mass fraction has been omitted as shown in the screenshot below:
Even though there are only vapor properties, and that the vapor mass fraction would be 1, if this value is left empty, the program could perform an extrapolation of the properties, thus affecting the film coefficient calculations and all the variables that depend on this value.
To avoid this issue, make sure that the vapor mass fraction field is always filled. In doing the calculations between different versions, the results will yield less differences.
Keywords: User specified properties, heat transfer coefficient, vapor mass fraction, different results
References: None |
Problem Statement: No vibration analysis is given for an un-baffled axial flow exchangers | Solution: Vibration calculations are performed for X-shell (un-baffled, but with support plates), but not for un-baffled axial flow exchangers, like an E shell for example.
Vibration is in general excited by crossflow over a tube bundle. With an axial flow bundle, it can be argued that excitation forces for vibration are largely absent, though there must clearly be an element of crossflow at the ends of the exchanger, for flow entry/exit via the nozzles. However, the program does not have any model for the regions over which such crossflow occurs. In general the crossflow may be well spread out in an axial flow exchanger, giving low crossflow(excitation) mass fluxes, though of course the unsupported length may be quite long.
Keywords: Vibration, Unbaffled
References: None |
Problem Statement: Why bubble and/or dew point does not match with Aspen Plus or HYSYS flash? | Solution: If you have properties data at only one pressure level or two pressure levels with significant pressure difference, then you may observe some difference in the bubble and/or dew point from Aspen Plus or HYSYS. The error comes due to error introduced during interpolation. There are two things you can do to minimize error.
1. Increase number of pressure levels.
2. Try to avoid a pressure level that is far away from inlet or outlet pressure.
Keywords: Bubble point, dew point, different, Aspen Plus, HYSYS
References: None |
Problem Statement: In Aspen Shell & Tube Exchanger, on Results | Thermal / Hydraulic Summary | Flow Analysis | Flow Analysis tab the program reports ''Bundle Entrance Flow Area'' and ''Bundle Exit Flow Area'' values in the Rho*V2 analysis section. How are they calculated? | Solution: The Bundle entrance and exit flow areas are output on Results | Thermal / Hydraulic Summary | Flow Analysis | Flow Analysis tab. They are calculated according to the methods given by TEMA. From TEMA 9th Edition (2007), the flow area calculations are described in details in Section 10 ''RGP-RCB-4.62 SHELL OR BUNDLE ENTRANCE AND EXIT AREAS'' under sub-set ''RGP-RCB-4.623 AND 4.624 BUNDLE ENTRANCE OR EXIT AREA'' on pages 10-15 and 10-16; the corresponding figures can be found on page 10-18.
They are measured directly at the top and the bottom of the tube bundle, where the shellside flow enters and exits the bundle. The calculation depends upon impingements plates being present or not, the impingement plate diameter or edge length (if impingement plates present), nozzle diameter (if impingement plates do not present), the diameter of the shell, the Outer tube Limit (OTL), the baffle inlet and outlet spacing, baffle cut orientation etc.
An equation is given in TEMA with explanations of nomenclatures. Approximations and some special considerations during the calculations are also stated at the beginning of this section in TEMA.
Keywords: Bundle entrance, Bundle exit, Flow area, Rho*V2 analysis, TEMA
References: None |
Problem Statement: Acoustic resonance is normally important only in gases as the speed of sound is normally too high in liquids. It occurs when the frequency of an acoustic wave in the heat exchanger coincides with the tube natural frequency. It should be noted that even if the acoustic wave does not cause tube vibration, it can lead to intolerable noise levels. However the combination of acoustic resonance and vortex shedding or turbulent buffeting frequencies with the tube natural frequency can be more serious since the acoustic effects tend to enhance the forces set up by other mechanisms. | Solution: The acoustic frequency is used as characteristic frequency in lock-in effect.
The acoustic frequency of the shell can be altered by inserting a deresonating baffle (also called detuning or acoustic baffle). This is a plate placed parallel to the direction of the crossflow to alter the characteristic length. Inserting the plate does not significantly affect the heat transfer or pressure drop. Users can find this feature in Shell & Tube Exchanger in the Input | Exchanger Geometry | Baffles/Supports | Deresonating Baffles tab.
Keywords: Acoustic resonance, Frequency, Vibration, Avoid
References: None |
Problem Statement: As described in | Solution: 127550, Aspen Shell & Tube Exchanger program conducts Rho*V2 analysis by calculating the Rho*V2 values in the various region inside the exchanger and comparing them with the TEMA recommended limits. If the TEMA limits are exceeded, ''Operation Warning 1341'' will be generated.
This is straightforward for single phase. However, if the flow is a two phase stream at the checking points (shell inlet/outlet nozzle, shell entrance/exit, bundle entrance/exit, tube inlet/outlet nozzles and tube entrance/exit), how does the program calculated local densities that will be used in Rho*V2 analysis, since the densities of the vapour phase and the liquid phase will be quite different from each other?
Solution
For two-phase streams, the density values that are used in Rho*V2 analysis will be the ''homogeneous'' density ρH, calculated from the follow equation:
ρH = x/ρG + (1-x)/ρL
Where:
x = Vapour Quality or Vapour mass fraction (Mass of vapour / Total mass of liquid and vapour)
ρG = Vapour density
ρL = Liquid density
Keywords: Rho*V2 analysis, ρν2, two-phase homogeneous density
References: None |
Problem Statement: AspenONE Process Explorer automatically associates a userID to a comment regarding a particular tag. Can I changed the userID of the comment? | Solution: All comments are added to the history repeat area of the record Comments defined IP_CommentDef. The username associated with the comment can only be edited programmatically using Aspen SQLplus by changing the field IP_CMT_SUBMITTER in the proper occurrence. Alternatively, the comment can programmatically be marked as bad, and a new comment with the other username can be inserted into history.
Keywords: username
comments
References: None |
Problem Statement: What is the fouling calculation option? How it is considered in maximum fouling calculations? | Solution: The fouling calculation option determines how the program will determine the maximum fouling on each side.
Program will default to the actual hot / cold side ratio.
Fouling calculations determine the exchanger fouling that would lead to a specified duty.
Some shell side or tube side fouling may be initially specified. One or both will be updated.
The various fouling calculation options are:
Set default
Adjust hot side fouling only
Adjust cold side fouling only
Adjust both sides based on fouling input
Adjust both sides using equal fouling
User can able to find above options in below path
Input/Program Options/Thermal Analysis/Fouling
Keywords: Fouling calculations, maximum fouling
References: None |
Problem Statement: The aspenONE Process Explorer (A1PE) search invoked from the A1PE Admin page can be stuck after a scan is initiated.
This is mainly due to the improper resource allocation for the Aspen Dispatch Service and the Apache Tomcat Manager Service.
In order to resolve this error, try the steps mentioned in this article. | Solution: Search can freeze or crash when Aspen Security is configured for the InfoPlus.21 Database.
In this case, the memory pool for the Tomcat Service needs to be increased.
1. Open Tomcat7w.exe located in <AspenTech Shared>\Tomcat7.0.57\bin. Click on the Java tab
Maximum memory pool is by default 256MB. The maximum memory pool can be increased up to 1024MB or 2048MB (2 GB) if available on the system.
The Initial Memory Pool can be doubled as well
Another parameter that can improve the performance is the Chunk Size. The Aspen Dispatch Service requests data from Process Data Rest in predefined chunbs. In versions prior to V8.8.1, the tags were published by the Dispatch Service. Starting in V8.8.1 the functionality was merged into Process Data Rest. Â The end user can specify the size of these chunks in the AtProcessDataREST.config file in the MetaDataDispatch Options Section
2. Open the AtProcessDataREST.config file present in C:\inetpub\wwwroot\AspenTech\ProcessData
i. Locate the MetaDataDispatch section.
ii. Rename the section title from “MetaDataDispatch� to “MetaDataOptions�
iii. Ensure that both the starting and ending tags are changed.
I.e. Starting (<Metadata Dispatch> change to <MetaDataOptions>),
     Ending (<MetaDataDispatch> change to </MetaDataOptions>
iv. Once the change is made, open the AtProcessDataREST.config file in internet explorer to confirm that the XML sections are visible and no edit errors exist.
v. Locate the “ChunkSize� parameter listed under the now “MetaDataOptions� section
Â
The Chunk Size can be reduced from 1000 to 500 in the AtProcessDataREST.config to reduce load.
The Chunk Size controls the number of tags that are posted to Search in each burst during a scan. Publishing groups of tags is faster than publishing one at a time. For slower systems, it is important to raise the available memory for Tomcat as shown in Step 1.
Please contact Aspentech support if either of these steps do not help in addressing the issue.Â
Keywords: A1PE
Search
Memory
Tomcat
References: None |
Problem Statement: Aspen Tasc (HTFS), Aspen Hetran (B-Jac) and Tasc+ seem to have many overlapping features. Which product should be used when and why? | Solution: Currently, there is some confusion among our customers over our current heat transfer products. We are going through a transition stage as we replace certain products.
Aspen Tasc+ is our new thermal design program for shell & tube heat exchangers. It does the complete thermal design (including vibration analysis) for shell & tube heat exchangers, double pipes, and multi-tube hair-pin exchangers. It has a bi-directional interface to our mechanical design program Aspen Teams. Teams is used to do the complete mechanical design calculation for all component thicknesses according to ASME Section VIII, Div. 1, CODAP, or AD Merkblatter codes. The next release of Teams will also include the new European design code EN13445.
Aspen Tasc+ was released in January 2006. It is a result of combining the best of our two former thermal programs TASC & Hetran.
TASC, Hetran and STX are being phased out. They will be supported through June 30, 2008. TASC-Mechanical has been retired and is no longer current with the ASME code. It has been replaced by Aspen Teams.
Where our new program Tasc+ has a bi-directional interface to Teams, as did Hetran, Teams has a one-way interface to the older TASC program. Teams can read in a .TAF file created from TASC for the automated transfer of information from the thermal to mechanical design programs.
NOTE for Aspen Plus and HYSYS users:
Since Tasc+ has run time interfaces to both HYSYS & Aspen Plus,
Tasc+ can be deployed as a unit operation in a flowsheet. In Aspen Plus,
Tasc+ can also be accessed from the HEATX block.
Keywords: Tasc, Tasc+, HTFS, BJAC, B-jac, B-Jac, Bjac, Hetran, STX, Aspen Plus, HYSYS, Teams, mechanical, vibration, rating, HEATX, HeatX
References: None |
Problem Statement: 在Aspen EDR (换热器)程序里，用户可以选择使用自定义的物质组分，作为单一物质或混合中的一部分。用户需要先在Aspen Properties (物性程序)里将自定义组分定义好，然后将Aspen Properties与EDR程序连接到一起。
用户可以在EDR内生成物性数据，并在相应界面里观测到具体数据。
但是，当完成连接后，把这些带有自定义组分的EDR文件进行保存后再重新打开此文件时，之前添加的自定义组分会消失不见。
此即决方案将讲述怎样使用、调整Aspen EDR(换热器)和Aspen Properties (物性)程序之间链接功能里的Advanced Options (高级选项)来解决此组分丢失的问题。 | Solution: 这个问题的原因，是因为用户之前选择了'Import existing Aspen Properties (.APRBKP) file'选项来连接Aspen Properties 文件和EDR文件。
用户应该选择?
Keywords: 用户自定义组分，非数据库组分，Aspen Properties (物性), Aspen EDR (换热器), 保存重新打开,,数据消失, CN-
References: an external Aspen Properties (.APRPDF) or Aspen Plus (.APPDF) file?选项来进行相应的连接操作，以解决自定义组分数据丢失的问题。
用户需要进行以下步骤
在Aspen Properties(物性)独立程序里面将自定义组分全面定义好，将其保存为一个*.aprpdf文件。详细细节请看解决方案119069。请注意，并不是所有的EDR用户都可以使用独立的Aspen Properties. 对于没有独立Aspen Properties使用权限的用户，您需要点击'Aspen properties Browser'按键，以打开Aspen Properties操作界面。
? 在EDR程序里，你需要到Input > Property Data > Hot stream Compositions > Advanced Options界面，选择第三个选项 'reference an external Aspen properties *.aprpdf or Aspen Plus *.appdf file'。
然后回到Input > Property Data > Hot stream Compositions > Composition界面，对每个组分的分率进行定义。
然后到Input > Property Data > Hot stream Properties > Properties界面，输入物性生成时的温度范围、压力条件和相应的作为物性生成基点的温度点。
最后，你可以点击'Get Properties'按键来生成物性数据。
附件里的EDR文件和*.aprpdf文件是一个例子。其中*.aprpdf文件包含一个自定义物质C2O3，然后连接到EDR模块的热流一端。在EDR文件被保存、关闭和再次打开时，此物质及其相应的物性数据仍然在EDR文件里，不会消失。
当你打开附件里的EDR文件时，你会看到物性数据在其中，但是相应的连接的路径不对。要解决这个问题，你需要重新链接EDR和相应的*.aprpdf文件。这是因为之前已经被保存在EDR文件里的*.aprpdf文件路径，和*.aprpdf文件在你的电脑上的保存路径很有可能不同。 |
Problem Statement: What kind of data can Aspen Search access and processed? | Solution: Aspen Search is able to detect and extract metadata from the following file types:
Filetype
Name
bkp
Aspen Plus
apw
Aspen Plus
hsc
Aspen HYSYS
doc
MS Word (2003)
docx
MS Word (2007+)
xls
MS Excel (2003)
xlsx
MS Excel (2007+)
xlsm
MS Excel (macros, e.g., Aspen Simulation Workbook files)
Note: ASW files are treated exactly like Excel files; no model metadata is extracted from these files.
ppt
MS PowerPoint (2003)
pptx
MS PowerPoint (2007+)
html
HyperText Markup Language
xml
Extensible Markup Language
zip
Aspen Search can extract metadata from the above files when they are contained within zip files. For more information, see Working with .zip and .apwz Files in the online Help
apwz
Compressed Aspen Plus files; for more information, see Working with .zip and .apwz Files in the online Help
IP.21 tags
Tags from IP.21
Aspen Search can also support some other formats, such as some image (e.g., .png, .jpeg, .tiff), video, audio, Java class file, Flash Video file, mbox, Open document, and electronic publication (.epub) formats.
Note: Although files in .pdf format can be stored on the file share, Aspen Search does not support full-text scanning of encrypted PDF files. To make it easier to find these files during a search, add text and other pertinent information in the comments section for the document.
Support for Non-English Characters
Aspen Search can index files for items which have Chinese, Japanese, or Korean characters in their folder or file name. The ability to index these files does imply that the URL returned in the search will properly open the document.
Keywords: supported file types
metadata
References: None |
Problem Statement: Where do I find the documentation which includes information about Lag Analysis in Collaborative Demand Manager (CDM) | Solution: When you installed CDM, you should have CAPHelp located here C:\Program Files\AspenTech\Aspen CAPs\CAPHelp\DM_Help\USEnglish
Keywords: None
References: None |
Problem Statement: Is there a way to bring B-jac (*.bjt) files into Tasc+? | Solution: When one opens a B-jac (.bjt) file in Tasc+ version 2004.2, an error will occur stating a Hetran license does not exist. However, the HTFS+ User Interface will continue to open.
As long as Results exist in the bjt file, the user can then click on Run - Transfer - Tasc+. The user can then switch to the Tasc+ application. No Hetran license is actually required.
Tasc+ version 2006 will also provide a standalone utility for converting Bjac (*.bjt) files to Tasc+ (.edr) files.
Keywords: Tasc+, B-Jac, b-jac, bjac, Hetran, .bjt, .edr
References: None |
Problem Statement: Aspen EDR does not accept the user input for Nozzle ID/OD under Geometry/Nozzle/Shell. | Solution: EDR does not allow geometry changes when the tube layout in Geometry Summary is in Use Existing Layout option.
To change the geometry, the tube layout is set to default as New Optimum Layout.
Keywords: Nozzle ID, thickness, tube layout.
References: None |
Problem Statement: Once a user adds a new analysis with a new date and saves the model, the old analysis is dropped from the list and cannot be selected again. How does feedstock analysis date works in AOS? | Solution: Any analysis data has a time stamp. AOS uses the available analysis fit for the model period. User can only see the 'active' analysis data from the screen. If delete the current active analysis, the nearest old analysis will be used as current active analysis. Any newly added analysis after the active analysis will be seen from the list.
For example, if the analysis dates are before the model active period, only the last one will be shown in the GUI even though all the data for all the analysis date exit in the database. Below demonstrates how this works in AOS.
In the example below the model period is from 8/1/2006 and lasts for 5 days.
Inside the database, Feedstock A180 has two analysis dates. Both are before the model start date. The last one 7/1/2006 is the latest one and is used in the current model period.
Open Feedstock screen and select A180 you will see 7/1/2006 is the only option shows in the Analysis Date.
list.
Once you delete the analysis data on 7/1/2006
After you confirm the deleting by clicking 'Yes' button, you can see from the Feedstock screen there is no analysis data
Save the model and open it again, you will see the analysis data of 6/1/2006 shows up.
Important: The data on 7/1/2006 has only been deleted from the memory when you close the Feedstock window after deleting it from the GUI. You need to save the model so that it can be deleted from database table. Otherwise, you will see it again when you open the model.
You can also add new analysis data. There are two scenarios,
1. If you add any new analysis before the model starting date, such as 7/15/2006. This analysis data will replace the old analysis and become the active analysis data.
2. If you add any new analysis after the model starting date, or even after the model period (i.e. 8/3/2006, or 9/1/2006), you can see the data from screen list
Keywords: Feedstock
feedstocks
Analysis
date
GUI
References: None |
Problem Statement: An element that has been marked as inactive in Demand Manager is still showing original history and working forecast data. | Solution: An override has put historical data back onto one of the attributes of the inactive element.
When an element has become inactive via the re-alignment process, the original history of the element is moved to the re-aligned element.
There is no need to do overrides to remove the history, the re-alignment process removes the data and places it on the re-aligned element.
If there is a requirement to reactivate the original element to an active status, it needs to be done via the re-alignment process. The re-alignment process moves all of the historical data to the new element. There is no reason to do an override that puts historical volume back on the element.
Note - there is no SCM table for re-aligned history - it is derived from the HIST tables.
Keywords: Override status error
Material
Location
References: None |
Problem Statement: What is the deresonating baffle? | Solution: A deresonating baffle is a type of baffles that is used avoid acoustic vibration problems.
When a heat exchanger has a flow-induced vibration problem, some corrective actions are available to reduce or eliminate the problem. First, verify that the vibration arises from shell-side flow, not from some other external source. Deresonating baffles are added when the problem is acoustic vibration.
According to Handbook Sheet VP4, deresonating baffles are often placed so that they divide the shell diameter into about one third and two thirds with the objective of preventing the fundamental frequency wave and its first harmonic from occurring. Dividing the shell diameter into two parts would only prevent the fundamental frequency wave.
All HTFS handbooks are available in HTFS Research Network library and accessing this library requires a license. If your company did not purchase the license, all the information in it would be proprietary to Aspen Tech.
Attached is some information about this type of baffles.
Keywords: De-resonating
De resonate
References: None |
Problem Statement: How to model electric heaters using Aspen Exchanger Design and Rating tool | Solution: Electric Heater has electric wires inside the tubes providing heating to the process fluid on the shellside. In Aspen Exchanger Design and Rating (EDR), users cannot directly model the wires. However, we can use the following workflow to model electric heaters
When the Shell & Tube Heat Exchanger in EDR is used to simulate electric heater, tube side is assumed as the heating element. Use thermal oil as component in the tube side for heat transfer modeling because the thermal oil does not have large temperature changes and can mimic the constant temperature of electrical wire. There is no need to input the tubeside flowrate and the only specification needed is the temperature/overall heat transfer duty.
Obviously, all the tube side calculation results should be ignored as in real case, there's no tube process stream while it is just a heating element. Please refer to the example for more details
Keywords: Electric Heater
References: None |
Problem Statement: What is the easiest way to get Aspen Plus data into Acol+, Aerotran, Hetran, Plate+, TASC, and Tasc+? | Solution: Here are the steps to follow:
1 - In Aspen Plus the Aspen Plus flowsheet, it is best to use a HeatX block. The HeatX block is preferable even over the Hetran and Aerotran blocks
2 - It is good practice to solve the HeatX block once in the Shortcut mode (see the shortcut radio button in the below figure). This will give you a good idea of the calculated outlet conditions and alert you to any physical property issues.
3 - On the HeatX Setup | Specification sheet, change the model to TASC, for Tasc+, ensure you are in Design mode. A successful design run ensures that all pieces of the interface are installed and configured correctly.
4 - On the HTFS+ Options | Input File sheet enter a file name complete with file extension. Please see the below figure for a list of all the possible file extensions. When running in the design mode, use a new file name.
5 - Run the Aspen Plus case and the interface will create the HTFS+ file complete with all the physical property data.
6 - Click on the HTFS+ Browser folder in the HeatX block and it will open a session of HTFS+ inside the Aspen Plus browser. You can navigate through the Tasc+, Hetran, Aerotran, Acol+, and Plate+ input and result forms just as you would in the standalone HTFS+ Browser.
7- Switch the Calculation Type field (see the top figure) to Simulation or Rating and re-run.
Please be aware that if you have never installed the HTFS+ product suite (Acol+, Aerotran, Hetran, Plate+, Tasc, Tasc+), this process will not work.
Keywords: Aspen Plus, ACOL+, Aerotran, TASC, TASC+, BJAC, HETRAN, data transfer, import, export
References: None |
Problem Statement: Why does TASC+ no longer appear available after installing the Teams 2006 update? | Solution: The early release of Aspen Engineering Suite 2006 was only targeted toward specific Teams and Icarus Users. For this reason when HTFS+ 2006 is installed, the only product that will show up in the menu is Teams (i.e. TASC+ and all the other products will not be available for the early release.
For those customers who still require TASC+ and other features, the version control utility (available via the Start/Programs/Aspen Engineering Suite/Aspen HTFS+ 2006/Version control utility menu item) will have to be used. Since only one version of HTFS+ can be run at one time, the version control utility can be used to toggle to whichever version is needed. Provided earlier versions of HTFS+ have not be un-installed, they should be listed as available options in the version control utility. Selecting an earlier version of HTFS+ will activate this version and deactivate the latest 2006 version.
Keywords: TEAMS, 2006 release, HTFS+, TASC+, version control utility
References: None |
Problem Statement: If multiple shells in series and parallel are simulated, are the reported pressure drops for one exchanger or for all of the exchangers combined? | Solution: The pressure drops are total pressure drops of all the exchangers in series (per parallel path).
For example, if you have a total of 6 exchangers; 3 shells in series in 2 parallel trains (that means 3 exchangers in each parallel path), then the pressure drops (shell side pressure drop and tube side pressure drop) are the total pressure drops for the 3 exchangers in series (in each path).
Keywords: pressure drop, series, parallel
References: None |
Problem Statement: Customer has AspenONE EDR V7.1 installed. APED is configured and ready to be used. Customer starts EDR V7.1 and attempts to fetch properties data from Aspen Properties data bases. He gets the following error:
Failed to create Aspen Properties Object, please install Aspen Properties from Aspen One DVD. Customer has problem running EDR due to APED problem. | Solution: Run Aspen Properties Registry Fix Utility from:
Start\Programs\AspenTech\Process Modeling V7.1\Aspen Properties and Select Aspen Properties 23.0
Keywords: EDR
Object
Properties
References: None |
Problem Statement: Why am I unable to enter the number of baffles for K and X shells? | Solution: In Aspen Shell &Tube Exchanger, K and X shells are considered to be unbaffled units and so do not allow baffles to be entered.
By default - Input | Exchanger Geometry | Geometry Summary is set to be unbaffled� and all other parameters for baffles are greyed out.
In order to prevent vibration, the workaround will be to enter mid space intermediate supports that will stiffen the bundle but not divert the shellside flow.
In Input | Exchanger Geometry | Baffles/Supports | Tube Supports tab set the Number of Supports for K, X shells
Keywords: Â K shell, X shell, Baffles, Unbaffled, Number of baffles.
References: None |
Problem Statement: This knowledge base article outlines how a user can schedule different synchronization operations within the Aspen Reporting Framework GUI so that the tasks will run automatically at the scheduled time. | Solution: Aspen Reporting Framework has ability to allow the users to schedule all the synchronization operations (Master Data Sync, Process Data Model and Process Cube) that are in the Schedule Operations tab within the Aspen Reporting Framework GUI. Note that by default there will not be any schedules attached to these components.
In order to schedule all the operations so that they can run automatically and synchronize the data click on the Pencil button before each component which opens up a 'Set Scheduler' dialog. In this dialog box select the daily frequency for the operation to be executed depending on the specific requirements. For example in the image below the Master Data Sync operation is set to run once every day at 3:00.
There is a description space that gives a brief detail with the specified frequency and from which date it will be effective. Once this is scheduled click the Save button at the bottom and after this the same Description within this dialog will be appended to the Aspen Reporting Framework GUI component Schedule Description field.
These schedules have to be configured individually for each synchronization operation using the same procedure mentioned above.
Important: Adding or modifying the schedules can be done only when all 4 services within the Schedule Operations tab in Aspen Reporting Framework GUI are all running.
Keywords: None
References: None |
Problem Statement: Where is the feature Symmetry 1 and Symmetry 2 from TASC in Aspen Shell & Tube Exchanger V8.8.2? | Solution: The Symmetry 1 and Symmetry 2 options from TASC has been replaced by Tube in reference location in the grid in Exchanger Geometry | Bundle Layout | Pass details tab.
If the user selects ‘Yes’, Symmetry 1 results are obtained. If ‘No’ is selected, Symmetry 2 results are obtained. These two options have the following meaning:
Symmetry 1 - For square pitch layouts the centre line has a tube line along it. For staggered layouts the first, third, fifth tube row etc is on the centre line.
Symmetry 2 - For square pitch layouts the centre line is between the tube rows. For staggered layouts the second, fourth, sixth tube row etc is on the centre line.
This means that for all tube patterns, except 90-Square ones, the user will always have tubes on the vertical center line. The difference between Symmetry 1 and Symmetry 2 consists in which row has the tube on the vertical center line (first or second).
Note that to enable the Pass Details tab Exchanger Geometry | Geometry Summary - Tube Layout must be set to New, match pass details.
Keywords: Symmetry, TASC , pass details
References: None |
Problem Statement: When I model a Shell & Tube Exchanger case either in Aspen HYSYS and export it to Aspen Shell & Tube exchanger, or I model the heat exchanger in the standalone program setting the vaporizer type as Flooded evaporator or kettle; the heat exchanger does not solve and the error message Input Error 1124 - The data input for Hot fluid location is unacceptable is shown.
How can this be resolved? | Solution: For Kettle Vaporizer type the allocation of the Hot Fluid has to be on the tube side. To resolve the error message, switch the streams so that the hot stream is on the tube side.
Keywords: Input Error 1124, Hot fluid allocation, Shell & Tube Exchanger, Flooded evaporator or kettle
References: None |
Problem Statement: Within the Aspen EDR programs, it is possible for users to create their own chemical properties databank for those fluids that are not found in any of the EDR databanks (B-JAC Databank, COM-Thermo or Aspen Properties).
The private databank can accommodate up to 400 different fluids, where details on how to enter the fluid properties are given in the on-line help under the Supplementary Programs and Databases | Private Chemical Databank.
There maybe a time when users wish to transfer this database to a different machine, where is the method described? | Solution: The databank is contained in three files;
D_IDPriv
D_FxPriv
D_VaPriv
These files will normally be in the folder where the program has been installed, e.g. 'C:\Program Files\AspenTech\Aspen Exchanger Design and Rating V7.2\Dat\PDA' and can be copied across.
However, the files could be located in a different folder if customized database files have been set. To check if customized folders are used go to the Tools | Program Settings | Files tab, where users can specify a folder to store the customized files. If a folder has been specified, then copy the above three files from this folder rather than those in the PDA folder.
Keywords: transfer private chemical properties data bank
References: None |
Problem Statement: In Aspen Shell & Tube Exchanger, on Results | Thermal / Hydraulic Summary | Flow Analysis | Flow Analysis tab the program reports ''Shell Entrance Flow Area'' and ''Shell Exit Flow Area'' values in the Rho*V2 analysis section. How are they calculated? | Solution: Shell entrance and exit flow area values are output on Results | Thermal / Hydraulic Summary | Flow Analysis | Flow Analysis tab. They are calculated according to the methods given by TEMA. From TEMA 9th Edition (2007), the flow area calculations are described in details in Section 10 ''RGP-RCB-4.62 SHELL OR BUNDLE ENTRANCE AND EXIT AREAS'' under sub-set ''RGP-RCB-4.621 AND 4.622 SHELL ENTRANCE OR EXIT AREA'' on pages 10-14 and 10-15; the corresponding figures can be found on page 10-17.
They are measured directly underneath inlet nozzles and above outlet nozzles. The calculation depends upon impingements plates being present or not, the diameter of the shell, the Outer Tube Limit (OTL), the nozzle diameter and clearance from the nozzle to the last row of tubes etc.
An equation is given in TEMA with explanations of nomenclatures. Approximations and some special considerations during the calculations are also stated at the beginning of this section in TEMA.
Keywords: Shell entrance, Shell exit, Flow area, Rho*V2 analysis, TEMA
References: None |
Problem Statement: As described in | Solution: 121775, users can transfer a heat exchanger case between Aspen Shell & Tube Exchanger and Aspen Shell & Tube Mechanical, by going to Run | Transfer, and selecting the desired program name.
However, this behavior will cause Aspen Shell & Tube Exchanger and Aspen Shell & Tube Mechanical programs to be opened at the same time. If the user has limited tokens that only permit one Aspen program (i.e. either Aspen Shell & Tube Exchanger or Aspen Shell & Tube Mechanical) to run at a time, users will see warning and/or error messages regarding the lack of license tokens (information about ''token sever'' can be found on page 98 in the ''Installation and
Keywords: Aspen Shell & Tube Exchanger, Aspen Shell & Tube Mechanical, Exchanger Data Transfer, License Error, Enough Tokens
References: Guide'' under the ''Documentation'' directory). The procedures below describe how the user can still transfer the data between these two programs. |
Problem Statement: What is the fouling calculation option? How it is considered in maximum fouling calculations? | Solution: The fouling calculation option determines how the program will determine the maximum fouling on each side.
Program will default to the actual hot / cold side ratio.
Fouling calculations determine the exchanger fouling that would lead to a specified duty.
Some shell side or tube side fouling may be initially specified. One or both will be updated.
The various fouling calculation options are:
Set default
Adjust hot side fouling only
Adjust cold side fouling only
Adjust both sides based on fouling input
Adjust both sides using equal fouling
User can able to find above options in below path
Input/Program Options/Thermal Analysis/Fouling
Keywords: Fouling calculations, maximum fouling
References: None |
Problem Statement: Why is a K Shell is not supported in Thermosyphon mode? | Solution: The reason why a K Shell is not supported in Thermosyphon mode is because the Tasc+ thermosyphon option assumes that the vapor and liquid leave from the same nozzle and flow via pipe work to the column. In K-shells it is assumed (in Tasc+) that the vapor and liquid leave via separate nozzles, so the Tasc+ K shell model and the thermosyphon option are not compatible with each other.
The thermosyphon in Tasc+ is essentially a simulation calculation wherein the flowrate around the cold circuit is calculated such that there is a zero pressure drop in the loop.
Note that a K shell is not a thermosyphon reboiler and it cannot be used to model one. Although Tasc+ does not limit the user to the listed choices, thermosyphon reboilers are usually either:
1. Vertical E type with the cold (boiling) fluid on the tube side
2. Horizontal G, H or X type with the boiling (cold) fluid on the shell side
Keywords: k shell, thermosyphon, thermosiphon, reboiler
References: None |
Problem Statement: How do I add my user to a Aspen Collaborative Demand Manager (DM) Model? | Solution: The following steps can be used. To add a new user (in this case, use your computer login id), update the following tables:
? USERIDS
USERINFO - Access type SAVE
RBTUSERS
RBTURMAP -(Super User: 1)
Afterwards, save the case performing File|Save As and give it another name.
Keywords:
References: None |
Problem Statement: Properties for hot stream or cold streams can be entered using three different databanks (B-JAC, COMThermo or Aspen Properties). However, if the User Specified option is chosen, when should one enter specific enthalpy? | Solution: Depending upon the phase on each process stream, only certain property information need be supplied. Specific enthalpy is required in the following cases:
1. For single phase fluids, duty (Q) is found by
Q = M Cp DT
In the above equation, M is the mass flowrate (kg/s), Cp is the specific heat capacity (kJ/kg) and DT is the change in temperature of the stream. This can be further changed to
Q = M Cp DT = M DH
Where DH is the change in enthalpy and is found from Cp DT.
Therefore for a single phase stream (liquid or vapor) the change in enthalpy can be determined from the specific heat and the temperature change (i.e. the specific enthalpy does not need to be entered). However, if it is, then this value is used in preference to that calculated from the fluid properties.
2. For two phase fluids;
DH = (1-x) Cpl DT + (latent heat)*(Quality change) + x Cpv DT
In the above equation, x is the quality on a mass fraction basis. For a mixture, the first term is the energy required to raise the liquid temperature, the second is due to the change of phase (quality change, dx) and the last term to heat the vapor. For a pure component, the term DT would be zero. The specific enthalpy is calculated as
Specific Enthalpy = (1-x) Liquid Phase Enthalpy + (x) Vapor Phase Enthalpy
Based on the above relation, one must enter the specific enthalpy and quality data when a phase change occurs (i.e. condensation or vaporization).
Keywords: specific, enthalpy, properties, condensation, vaporization, vaporisation, phase, change
References: None |
Problem Statement: How do you specify the properties for the heat exchanger materials when they are not in the databank? | Solution: When a material is in the Aspen Tasc+ databank, you can click on the TOOLS pull down menu and then click on DATA MAINTENANCE | MATERIAL DATABANK.
When you see the diagram of the heat exchanger, click on the DATABANK pull-down menu and select one of the databases and begin perusing the current materials.
If you don't find the material you are seeking in any of the Aspen Tasc+ databanks, then do the following:
1. In most cases, exchanger materials have minimal effect on exchanger performance, so selecting a database material that has similar properties is often an acceptable remedy. You may want to update the material cost for the substitute material as this will make a significant difference in the calculated cost of the heat exchanger and could potentially alter the design optimization (which has an objective function to select the heat exchanger design case with the lowest cost).
2. If you would prefer to add your own material to Aspen TASC+, there is a USER material database. The steps for using this are as follows:
a) Open Materials Database by selecting Tools / Data Maintenance / Material Database form the Aspen HTFS+ User Interface.
b) Open one of the existing Code material databases, such as ASME, from the Database Menu option.
c) Select a similar material in the Code database to the private material you wish to create. This will act as a template for the new material.
d) Select Property / Copy to copy the contents into the buffer.
e) Select Database / User. If no user materials exist in the database, you will be asked if you wish to create a new material. Answer Yes and set the user database number for the new material. Your new material in the database will be displayed with the existing properties being used as a template. Proceed to step g)
f) If user materials already exist, your existing database items will be displayed. To copy the template properties, select Property and Paste and then select a number new material reference number.
g) Now modify the template properties to generate your new material. If you have selected a very similar material, you may only need to modify the material names and the allowable design stresses.
h) Once all changes have been made, select Save to update the database. Now this new user material may be referenced from any of the Aspen HTFS+ programs.
Keywords: HTFS+ Materials database, material databank, user database, user specified
References: None |
Problem Statement: How can I create Feedstocks in Aspen Olefins Scheduler? | Solution: Below arethe step by step instructions for adding a new feedstock.
Initial requirements:
A.- Configure all feedstocks in the Aspen Furnace Configuration Utility prior to creating a new feedstock in AOS.
B.-Information about the molecular Composition or PIONA analysis for each new feedstock is needed.
1.-To add/create a new feedstock, from the Event interface,
Click Model | Feedstocks to display the Feedstocks dialog box.
2.- Click ?New? button, a ?new? feedstock will be added to the list with the default name F (number), for example F1, as shown below. To rename the default product name, select it and type the new name. Enter the description of the feedstock in the ?Description? field.
3.- Click ?Add Analysis? button and enter the date of the lab analysis:
4.- Add either the molecular composition (click ?Molecular Composition? button or the PINA analysis (click ?PIONA? button).
Molecular Composition PIONA
5.- If you entered the PINA analysis, click ?Covert Entered PINA to MC? to convert the PINA analysis to its molecular composition. AOS calculates the Molecular Composition and then recalculates the PINA values from the calculated Molecular composition and displays the calculated PINA values in the calculated column
The Molecular composition is calculated on one of two ways:
- AOS uses the SPYRO models if SPYRO is installed on the local computer
- If SPYRO is not installed on the local computer, AOS uses a regression set created against the SPYRO model
6.- Click ?OK? button to SAVE your changes in ?memory? and exit the dialog box. Click ?SAVE? model option located on the toolbar, to save changes in the database.
Keywords: None
References: None |
Problem Statement: Unable to print TEMA sheets within TASC+ after receiving ERROR 482 and BLABEL1 messages. | Solution: This is usually caused by an internal network problem (i.e. there are disruptions on the network or to the network printer that the TEMA sheets are being printed from). To resolve this issue, ensure that all network disruptions have been reconciled on internal networks before trying to print out TEMA sheets.
Keywords: TEMA sheets, print, error 482, network
References: None |
Problem Statement: How do I change my language in Collaborative Demand Manager (CDM)? | Solution: The change the CAP language, select Options > Settings and select your favorite language from the Current Language drop down.
Keywords: None
References: None |
Problem Statement: How to I use the interactive tube layout feature to customize tube layouts? | Solution: The steps are as follows (if in Rating/Checking mode then skip to step 3):
1) Run Aspen Tasc+ in design mode to determine the specific heat exchanger geometry for your process.
2) Click on Run - Update file with geometry to automate the transfer of information to the Input - Geometry section to satisfy the Checking/Rating requirements.
3) Click on Input - Exchanger Geometry - Geometry Summary - Tube layout tab.
4) If you wish to delete a tube or tube row, then click with the right hand mouse button on the appropriate tube or tube row. The row will become highlighted and you will have a pull down menu of options to select from. Select from either delete tube or delete tube row, whichever is appropriate.
5) It is also possible to modify other components associated with the tube layout such as sealing strips, tie rods, baffle cuts, etc. from this same screen display.
Keywords: heat exchangers
References: None |
Problem Statement: How do I get the desired symmetry in Tube Bundle Layout? | Solution: Starting Aspen Shell & Tube Exchanger V7.2, User can get desired Tube Layout symmetry using the new layout options incorporated in Aspen Shell & Tube Exchanger application. Following instructions will guide the user setting up these new tube layout parameters.
1. Go to Input | Exchanger Geometry | Bundle Layout | Layout Parameters | and select Specify Pass Details for Tube Layout Option, please see the picture below.
2. Next on the same page, set the Pass Layout, Pass Layout Orientation, Tube Layout Symmetry and Bundle Limit Symmetry as required, please see the picture below.
3. Finally move onto Input | Exchanger Geometry | Bundle Layout | Pass Details TAB and adjust the number of rows and columns and also modify the number of tube rows per pass so that the layout is symmetrical or as desired. As you modify the number of rows and columns and tube rows per pass, the program calculate the number of tubes it can fit in and also display the tubes per pass and total tubes. Run the program and review the layout. Please see the picture below.
Keywords: Tube Layout, Bundle Layout, Pass Details, Symmetry, Layout Parameters, Tube Layout Symmetry.
References: None |
Problem Statement: In Aspen EDR programs, there are some features that are designed to assist in users' inputs.
For example, when users finish input on one tab they may want to be navigated to the next tab that requires inputs. They may also want to be reminded by the program that which input sections are completed and which are not. | Solution: There are similar features in Aspen EDR programs.
? The ''Next'' button is for navigating users to the next form that requires inputs. This will help users to go through the various inputs on different tabs step-by-step.
? The ''Go Back'' ''Go Forward'' buttons are for tracking users' views of different forms on the tree-menu that haven been previously accessed. Clicking the ''Go Back'' button will navigate users from the current form to the previous form. Then if users click the ''Go Forward'' button, they will be navigated forward to where they were before clicking the ''Go Back'' button.
? The ''previous Form'' ''Next Form'' buttons will navigate users to the previous (higher in the tree-menu) or next (lower in the tree-menu) form in the tree-menu list.
? If any inputs on any tabs are not completed, a red cross will keep showing up on the corresponding tab and folder, until the inputs are completed.
? A blue background in the input field indicates that the input is being required.
Keywords: Go back Go forward, Next, Previous form, Next form, navigation, complete input, red cross, blue background.
References: None |
Problem Statement: Consider the case where liquid enters around the periphery of a tube at a constant flow rate with gas flowing upwards in the tube. At low gas flow rates, the liquid falls down the tube in a film and passes out from the bottom of the tube. As the gas flow rate is increased, a condition is reached where large waves are formed on the film and liquid is carried partly upwards beyond the injection point. This phenomena is called flooding and the gas velocity at which this occurs is called the flooding velocity. As the gas flow is further increased, liquid flows both upwards and downwards from the point of injection, until ultimately all the liquid flows upwards. If now, the gas velocity is decreased, a point is reached where the liquid film begins to creep below the injection point and this condition is known as flow reversal. | Solution: In a vertical thermosiphon reboiler there is the possibility that in the axial outlet nozzle or tube exit, the vapour velocity may not be sufficiently high to lift the liquid out of the reboiler. This phenomenon is related to flooding and flow reversal in two-phase flow.
From Results > Thermal / Hydraulic Summary > Flow Analysis > Thermosiphons and Kettles tab, the flow reversal and flooding criterion are given.
Aspen Shell & Tube Exchanger applies the Wallis (1962) criterion for flow reversal. The criterion provides a lower limit on the dimensionless vapour velocity
where
is the superficial vapour velocity in the tubes and is the inside diameter of the tubes. The superficial gas velocity at the exit of the tubes can be found from
In addition the Wallis (1962) criterion for avoidance of flooding at the top of the tubes is applied
The Kutateladze Number is used for the outlet nozzle, where for the flow reversal criterion the number should be greater than 3.2.
Accurate prediction of flooding and flow reversal is not possible and these criteria should be regarded as approximate guidelines that should preferably be exceeded by a significant margin in design.
Nomenclature
Inner diameter of tubes, m
Gravity, m/s2
Kutateladze number in the outlet nozzle
mass flux, kg/m2s
Dimensionless velocity
Superficial velocity, m/s
Surface tension, N/m
Gas density, kg/m3
Liquid density, kg/m3
subscripts
g Gas
l Liquid
Keywords: Flooding, flow reversal
References: s
Wallis, G.B. (1962), The transition from flooding to upwards co-current annular flow in a vertical pipe,
UKAEA Report AEEW-R142. |
Problem Statement: When in ?Rating / Checking? or ?Simulation? mode under Input | Problem Definitions | Application Options | Application Options tab, the Pass Details can be set under Input | Exchanger Geometry | Bundle Layout | Pass Details tab. From this input form, details can be entered specifying the number of rows and columns of tubes in every pass and hence all the tube locations.
Sometimes this input form may be ?greyed? out, where this | Solution: explains how to activate the form.Solution
From the Input | Exchanger Geometry | Geometry Summary | Geometry tab, for the Tube Layout there are a number of options to specify the location of the tubes in the bundle;
New (optimum) Layout: A set of internal rules is always used in Design mode, where exchanger geometry must be found and the number of tubes and passes determined. This is also used by default in Performance modes (Simulation and Checking), where the geometry is in principle known. Each time the program is run, the tubesheet layout is drawn based on the geometry entered in the input forms.
New, match tubecount (obsolete): Uses the method above, but then artificially removes tubes.
New, match pass details: Pass details specifications are provided using a simple method of specifying the number of rows and columns of tubes in every pass region, and hence all tube locations.
Use existing layout: Can also be used to simply continue using a layout generated by any of the other methods. Interactive graphics are available to add/delete tubes, move tube pass regions and other bundle furniture to any desired location.
When the ?New, match pass details? is selected, then the Pass Details input form is activated and the number of tube rows and columns can be entered for the various passes.
Keywords: pass layout, pass details, tubesheet layout, bundle layout
References: None |
Problem Statement: How do I export a TEMA sheet to Excel? Sometimes I have problems running the default template when I export. | Solution: To export a TEMA sheet to Microsoft Excel:
1. Go to File/Export to/To excel using the specified template
2. When it specifies what template to use, select
AspenTech\Aspen HTFS+ 2004.2\Dat\Template\Tasc+TEMAsheet.xlt.
If that template does not work, create a blank excel sheet and reference that file.
3. When prompted to name the file, go ahead and name the xls file.
If for some reason there are sti problems exporting an Excel file select the export to a word document and then copy and paste into a blank excel sheet.
Keywords: excel, HTFS, export, word, TEMA
References: None |
Problem Statement: The effective tube length is the length for heat transfer. In fixed tubesheet arrangements, the effective length is the tube length minus the tubesheet thicknesses and projections beyond the tubesheet as can be entered from Input > Exchanger Geometry > Shell/Heads/Flanges/Tubesheets > Tubesheets tab. This | Solution: explains other geometry items that should be considered with a K or X- shell. Solution
In an X-shell, the shellside inlet flow (if condensing) normally enters at the top of the shell and is distributed along the tube length to then flow diametrically across the bundle to then be removed at the bottom of the shell. To aid uniform flow distribution along the length of the exchanger, multiple nozzles may be used.
For a K shell, the cold shellside fluid enters at the bottom of the shell and flows diametrically across the tube bundle where it is heated by the tubeside stream.
The tube effective length is given in Results > Mechanical Summary > Exchanger Geometry > Tubes tab.
For an K or X-shell, if U bends are used, then in Shell & Tube V8, by default a “Support only” is selected for the “Support or blanking Baffle at rear end” from Input > Exchanger Geometry > Baffles/Supports > Tube Supports tab. The length of tube beyond the support/blanking baffle is then considered for heat transfer. If a Normal or Rigid support is selected, then the distance beyond the blanking/Support baffle is deducted from the tube length.
If cases are bought forward from an older version of Shell & Tube(older than V8.0) and a blanking baffle has been set as default for a *XU or *KU units, then the effective length will be lower due to the distance entered beyond the support baffle, than V8 onwards, where this is not subtracted. The change in effective length may result in a difference in the area ratio of duty performed.
Keywords: Effective Length
References: None |
Problem Statement: The customer has a mixed phase (vapor & liquid), multi-component (wide boiling) hot stream he wants to condense. He wants to enter the vapor phase composition and the liquid phase composition of the hot fluid. Hetran will allow him to enter composition for both phases only when he uses the narrow range composition option. | Solution: Yes, this is by design. The user has two additional options: Multi-component - curve specified by the user where he can do the same thing or Multi-component - curve calculated by program where the program based on the VLE calculations will determine the quality.
Keywords: Hetran, Tasc+, multi-component
References: None |
Problem Statement: Can I design a spiral heat exchanger in Aspen TASC or Tasc+? | Solution: Aspen TASC, Tasc+, or Hetran can not design or rate spiral heat exchangers.
Keywords: Spiral Heat Exchanger.
References: None |
Problem Statement: Is it feasible to design electrically heated exchangers using Aspen Shell & Tube Exchanger? | Solution: Aspen Shell&Tube can indeed be used to design electrically heated ''shell and tube'' heat exchangers although the process is a little complicated and it does have some limitations. Advice about this procedure is given below.
? Electrically heated units differ from traditional units in that they have a constant heat flux rather than heat flux limited by the temperature of the hot stream (the element temperature will increase in order to keep a constant heat flux). The important thing therefore is to ensure that the heat flux is constant along the length of the heat exchanger. Shell&Tube does not handle this constant heat flux concept so it has to be done manually by changing the temperature differences.
In general the limitations mean that it will only be able to model single phase (with approximately a straight line heat release curve).
Shell&Tube requires two streams so you need to supply the data for a ''dummy'' tubeside fluid. It is important that this fluid plays no part in limiting the design of the heat exchanger. Thus the tubeside coefficient, wall resistance and pressure drop should be such that they do not affect the overall design (high coefficient, low resistance and high allowable pressure drop).
Quite often the heated length is less than the element length. Allow for this when specifying a maximum tube length in design mode.
Elements are usually U shaped. Do not model this as a two pass unit in Shell&Tube use single pass.
Often the pitch between elements is not constant (eg they are closer together near the shell wall or they are non standard). This cannot be modelled with Shell&Tube which can only handle a constant pitch of the traditional 30, 45, 60 or 90 degree type.
Please note that experience will be required to estimate whether you will have any ''hot spots'' if it is a baffled unit (very often electrically heated units are not baffled in order to avoid this possibility).
The calculation procedure is basically as follows:
1. Carry out the initial design in Design mode (if required). Ensure that the hot fluid is on the tube side.
2. For the tubeside fluid, pick one of the fluids in the databank (eg air or water) and make it high pressure (say 50 bar) with a high allowable pressure drop (say 10 bar). Default the flowrate so that it is determined by the inlet and outlet temperatures. You may need to vary these values.
3. Select a thin wall thickness and enter a high thermal conductivity for the wall material. The tube outside diameter should be equal to the element diameter.
4. Enter a constant very high tubeside coefficient (for liquid, two phase and vapour) on Input | program Options | Thermal Analysis | Heat Transfer tab (for the hot side).
5. For the tubeside inlet and outlet temperatures, initially select the inlet temperature to be approximately equal to the maximum allowable element temperature. Set the outlet temperature so the temperature difference between the two streams is the same at both ends of the exchanger, which should approximately give a constant heat flux.
6. Carry out the design. Select a design where the area ratio is greater than 1.0 so that it allows for the unheated length of the elements.
7. Convert this design to a checking case and run the case. (More details of this implementation can be fund inSolution 121775.)
8. On Results | Calculation Details | Analysis along Shell | Interval Analysis/Plots tab, review the ''Interval analysis along the Shell'' output and check that the heat flux is approximately constant in each zone. You will often find that there are now two problems - the heat flux varies as you pass down the exchanger from one end to the other and/or the maximum heat flux has been exceeded.
9. If the heat flux varies from one end to the other, increase the lower temperature difference between the streams (at the end where the flux is lowest) and/or reduce the higher temperature difference between the streams (at the end where the flux is higher).
10. If the heat flux is larger than the maximum allowable heat flux, reduce the temperature difference at both ends of the exchanger by the same amount.
11. Rerun in checking mode, iterating over points 7 to 10 until a reasonably constant, acceptable heat flux is obtained. The area ratio must be at least equal to the element length divided by the heated length.
The process is now finished.
Keywords: Shell & Tube Exchanger, Tasc+, electric, heating, shell and tube, electrically heated exchanger
References: None |
Problem Statement: How is the turbulent buffeting frequency calculated? | Solution: The turbulent buffeting frequency equation used by Aspen Shell & Tube Exchanger is the same used in the TEMA (Tubular Exchanger Manufacturers Association) standard and HTFS:
where:
do -= outside diameter tubes (inches)
xl = Pl / do
xt = Pt / do
Pl = longitudinal pitch (inches)
Pt = transverse pitch (inches)
V = crossflow velocity (ft/s)
The equation includes a constant multiplier due to unit conversion. For SI calculations, the (12) number should be ignored and the velocity should change to (mm/s).
Pl and Pt are calculated based on the figure below:
Hence,
Pl = pitch x sin (30)
Pt = 2 x pitch x cos (30)
Then, the turbulent buffeting frequency value from the equation above can be checked against Aspen Shell & Tube Exchanger.
The turbulent buffeting frequency can also be calculated as the frequency ratio (Ft/Fn) multiplied by the natural frequency (Fn).
These values can be found in the program under Results / Thermal hydraulics Summary / Vibration & Resonance Analysis / Resonance Analysis (HTFS)
Keywords: turbulent buffeting frequency, longitudinal pitch, transversal pitch
References: None |
Problem Statement: What does Longitudinal fin cut and twist length refer to? | Solution: The tube has cuts through the fin channels circumstantially at specified intervals along the tube length. The fins are then bent (or twisted) on one side of each cut, creating a discontinuity that promotes turbulent fluid flow, thereby enhancing heat transfer efficiency.
The Longitudinal fin cut and twist length input located on Inputs / Exchanger Geometry / Tubes / Fins refers to the distance between these cuts.
Keywords: Longitudinal fin, cut and twist length, fins
References: None |
Problem Statement: How do I resolve error message Improper Aspen Properties Specifications? | Solution: This message appears when you run the EDR program with Aspen Properties selected as the physical property package on the Hot/Cold Stream Compositions datasheet while no component has been selected.
To resolve the issue, you have to add the components by clicking on the Search Databank... at the lower left corner of the Hot/Cold Stream Compositions | Compositions datasheet.
Keywords: Improper Aspen Properties Specifications, run, EDR
References: None |
Problem Statement: How do you select Stainless 2205 tubes in Materials of Construction? | Solution: Exchanger Design & Rating has alloy 2205, but listed name in database is not an ASME name. You can find this material if you go to Construction Specifications | Materials of Construction | click on Databank Search | Advanced tab | on SEARCH select ‘'Alloy Design/UNS No, and on LIKE select S32205 (there will be 9 matches for that material, the difference lies in the Product Form, select the most appropriate one depending on your application). In addition, there are other UNS compositions that match duplex 2205, such as S31803 (also has 9 matches).
Keywords: Materials of Construction, stainless, 2205
References: None |
Problem Statement: The PROPS program in Aspen HTFS+ is not returning results for pure components or mixtures. | Solution: Make sure during installation that Aspen HTFS+ sub-features are installed. Failure to install all sub-features will result in the features appearing to be available and active, but they will not run.
Keywords: Props, results, missing
References: None |
Problem Statement: Due to some problems in the installation procedure of the early version of HTFS+, some HTFS+ DLLs can not be unregistered or re-registered (after being updated by a patch for example).
As a result:
HTFS+ might not run normally
HTFS+ Data Browser can not be opened from Aspen Plus in a HEATX block
An HTFS+ block included in an Aspen Plus simulation will return an error at run-time:
** ERROR WHILE EXECUTING UNIT OPERATIONS BLOCK: W2717 (MODEL: HEATX)
FLOATING POINT ERROR IN TASC
BLOCK BYPASSED
When running the utility BjacRegClean.exe, a list of DLLs remain , even after clicking on the Clean Up button | Solution: Change permissions in Windows registry to \HKEY_CLASSES_ROOT\TypeLib:
1. Log on the machine as a local administrator.
2. Open the windows registry (if you do not know how to do it, you should not be trying to address this problem yourself, ask your IT to do it for you).
3. go to \HKEY_CLASSES_ROOT\TypeLib, do a right-mouse button click on that node and select Permissions.
4. Assign Full read and write permissions to the Administrators group of your machine.
5. Close the Regedit.
6. Go to C:\Program Files\AspenTech\Aspen HTFS+ 2004.2\XEQ, run BjacRegClean.exe and do a Clean Up
7. Finally, you can carry out an uninstall, or re-register the controls and DLLs running regcontrols.bat from the same folder.
Keywords: Registry
BjacRegClean
FLOATING POINT ERROR
References: None |
Problem Statement: What is Tasc+? | Solution: Tasc+ combines Aspen HTFS with Aspen B-JAC. Click on this link to find out more: Tasc+ Overview.
Keywords: TASC; Shell & Tube; Heat Exchange; Design; Rating
References: None |
Problem Statement: I am getting Operation Warning 1336, saying that I might have a poor heat transfer since the crossflow fraction on the shellside is less than 30%, how can I troubleshoot this? | Solution: Cross and Window flow contribute to the heat transfer in a heat exchanger and where there is a leakage, the cross flow fraction decreases. The program will give a warning message if the cross flow decreased to less than 30% at any point of a heat exchanger indicating that this issue is one of the causes that gives a poor heat transfer coefficient on the shellside.
You can review these fractions under Results | Thermal / Hydraulic Summary | Flow Analysis.
The leakage could be in the baffle/ Shell, tube/ Baffle and other bypass' clearances
To deal with this problem, there are a few recommendations:
A? Change the number of baffles and the increase the baffle pitches
A? Ensure that the baffle cut orientation is horizontal when the shellside stream is one phase and vertical when the shell side stream is two phase.
A? Decrease the bypasses' clearances mentioned above and specify them according to TEMA standard. If you leave the clearances in the program empty, it will use the numbers according to TEMA.
A? Add sealing strips to avoid any bypass between the bundle and the shell
Keywords: Crossflow fraction
References: None |
Problem Statement: I am trying to change the input information in my Aspen Tasc+ simulation. Why am I not able to change the Shell Type, Shell Diameter, Number of Tube Passes, etc.? | Solution: If you cannot change certain items like Shell Type, Shell Diameter, Number of Tube Passes etc, check the item Tube Layout on the Input > Exchanger Geometry > Geometry Summary > Geometry tab to see if it is set to Use existing layout. If it is, and you need to change any of these values, change the item to Create a new layout.
The normal use for Use existing layout is to make small refinements to an existing diagram (eg replace tubes by tie rods or remove tubes). When you are changing items like the shell diameter, number of tube passes or return head type (which can affect the bundle/shell clearance and therefore the tube count), you need to change the item to Create new layout so that a new tube layout will be created every time you run Tasc+. Once you have finished changing the major items you can then swap back to Use existing layout and continue to make small refinements.
Keywords: tube layout; tasc; shell and tube; heat exchanger
References: None |
Problem Statement: Is it possible to specify variable number of tubes per pass? | Solution: Starting with Aspen Shell & Tube exchanger V7.2, it is now possible to specify and evaluate the variable number of tubes per pass.
The Pass Details facility can be used either to exactly match an existing layout or explicitly to specify a bundle with different numbers of tubes in each tube side pass. Heat transfer and pressure drop calculations are now based on the exact number of tubes in each pass, so it is possible to investigate cases where significantly different mass fluxes in each tube side pass might have a beneficial effect on heat transfer or pressure drop.
To specify the Variable number of tubes per tubeside pass,
1. Go to Input | Exchanger Geometry | Bundle Layout | Layout Parameters and select Specify Pass Details for Tube Layout option.
2. Next go to Input | Exchanger Geometry | Bundle Layout | Pass Details and specify the number of tubes per tube pass.
Keywords: Pass Details, Tube passes, Number of tubes, Bundle
References: None |
Problem Statement: Different nozzle types can be set in Input | Exchanger Geometry | Nozzles | Shell Side Nozzles for the ?Nozzle / Impingement type?. Here dome or impingement plates maybe set that protect the tubes directly under the inlet nozzle from damage due to vibration or erosion.
For a dome nozzle the piping or normal nozzle size can be specified by the Actual ID size, while the dome diameter is specified in the Dome/Belts tab. However, if these values are not entered then the program will determine these, using the method described. | Solution: If the nozzle and dome size have not been entered by the user, then the method to determine the sizes is as shown below.
Dome
The dome diameter is based upon the smaller of twice the nozzle diameter or the mean of the nozzle diameter and the shell diameter, i.e., ?* ( nozzle diameter + shell diameter).
Nozzle
The nozzle diameter is either sized based on the target percentage of the total pressure drop ( Input | Program Options | Design Options | Process Limits tab) or the maximum RhoV2 limit (Input | Exchanger Geometry | Nozzles Shell Side Nozzles tab).
The size of the nozzles and domes calculated can be found from Results | Mechanical Summary | Exchanger Geometry | Basic Geometry.
Keywords: Dome size, Dome diameter, Dome nozzle
References: None |
Problem Statement: In the Design modes of Aspen Shell and Tube Exchanger, some basic geometry can be selected together with the duty requirements and the pressure drop constraints for the shell and tube side. The program then will look at various geometries that will meet the area requirement (duty) and the pressure drops and present results for the minimum cost design (default setting).
From Input | Program Options | Design Options | Geometry Limits tab, the shell diameter or tube length can be set to minimum and maximum limits to be used for the design together with an increments step. However, some times when the program is run, you may notice that the shell diameter or tube length does not match the values set. This | Solution: explains why this may occur.Solution
British / US standard pipe sizes range from 6, 8, 10, 12, 14, 16, 18 and 24 in nominal bore (152, 203, 254, 305, 356, 406, 508 and 610mm) for the shell diameter.
From the standards of the Tubular Exchangers Manufacturers Association (TEMA) standard tube lengths are 8, 10, 12, 14, 16 and 20 ft (2.44, 3.05, 3.66, 4.27, 4.88 and 6.1m) and tube outer diameters range from 0.25 to 2 inches (6.35 to 50.8mm).
From Input | Problem Definition | Application Options, the input item 'Select geometry based on this dimensional standard' can be used to determine the dimensional standard used for the vessel thicknesses and tube lengths. Changing to SI or US will give a different range of default values in the Geometry Limits tab.
Setting US units as the dimensional standard and SI in the Geometry limits will result in the program designing to the nearest US standard pipe size and length in the range given in the Geometry Limits.
In addition, from Input | Program Options | Design Options | Geometry Limits tab, be careful with the input item 'Use pipe for shells below this diameter'. Smaller shells diameters are normally selected based on standard pipe sizes, while larger shells are assumed to be welded and can thus be of any required diameter. You can reduce the limit up to which the standard pipe sizes are used if you require.
If you are consistent in the units on both forms and the 'pipe for shells below this diameter', then the design will match the geometry limits as you may see from the Results | Results Summary | Optimization Path.
Keywords: design, standards
References: None |
Problem Statement: How do I install Aspen Tasc+? | Solution: With the release of aspenONE, you will have received a set of DVDs. Discs 1 to 6 are the product installation DVDs organized according to product family. Aspen Tasc+ is installed as part of the Aspen Engineering Suite (AES) set of products and can be found on DVD number 6.
Installing using the AspenTech Installation Browser:
1. Load Disc 6 into your DVD reader.
2. The Installation Browser should launch automatically. If it does not, select Run from the Start menu and in the Run view type d:\setup.exe, where d: is your DVD drive.
3. Read the attached word file for detailed step by step installation procedure. Aspen Tasc+ is in the Aspen HTFS+ folder.
Keywords: Tasc+
Tasc Plus
tasc Plus
Install
References: None |
Problem Statement: Where can I find the crash log file if Aspen Exchanger Design & Rating is crashing? | Solution: When EDR crashes, it generates log files. You can find this file at following location
C:\Users\[username]\AppData\Local\AspenTech\AspenEDR vX.X
You may need to enable hidden folders on your computer to navigate there:
1. Open control panel
2. Click on appearance and personalization
3. Click on folder options
4. Go to the view tab and toggle the Show hidden files,folders, and drives
Keywords: EDR, error log, crash log, crash, freeze, log file
References: None |
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