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Q. I'm having trouble using the ANMRES macro to animate FLOTRAN results with Remeshing active. I get a message complaining that there is only one substep on the results file. What is wrong?

A. The animation macros involved require that there be two or more sets of results on each of the jobname.rfl0nn files that are created. This is reported as defect 25229.


Q. I'm having trouble using the ANMRES macro to animate FLOTRAN results with Remeshing active. I get a message complaining that there is only one substep on the results file. What is...

Uninstalling Workbench 8.0 AFTER Installing Workbench 8.1 Causes Program Errors, (i.e Error occurred in mesher module).


A conflict in GUIDs causes the Workbench 8.0 Setup program to unregister files required by Workbench 8.1<br><br> ...

A model of a cast iron part has a region that experiences significant tensile yielding. This model is having severe convergence difficulties, terminating with an error in element formulation. However, the deformations are not that extreme. Why is this model having so much trouble converging?


A significantly improved Cast Iron material model was implemented in the first service pack for ANSYS 8.1 (ANSYS 8.1 A1, UP20040609). This improved material model is much more robust, especially...

The following error messages were obtained when trying to start CFX-Mesh on a Windows platform from Workbench 8.1 (in two pop-up files entitled Script Error and Internet Explorer Script Error):

Script Error
Line: 10052
Char: 6
Error: Object doesn't support this property or method
Code: 800a01b6
Source: Microsoft JScript runtime error
Script: consts.Shell.CurrentDirectory = m_projectPath;

Internet Explorer Script Error
Line: 203
Char: 2
Error: Could not complete the operation due to error 80020101
Code: 0
URL: file://C:Program FilesANSYS Incv80
AISOLStartPageLanguageen-
usStartPagesProjectPage.html

I have Internet Explorer version 5 installed on my machine.


The version of Internet Explorer needed for CFX-Mesh is version 6.0. Updating the version of Internet Explorer to version 6.0 resolves the problem.

How can a user export DesignXplorer or DesignXplorer-VT data to an Excel file?


In DesignXplorer 8.1, use the following macro to export the data.<br><br> 1. Save the attached file to Designs_to_excel.js<br> 2. In DesignXplorer, select Tools > Run...

I am not able to locate a menu or option for choosing cylindrical or spherical coordinate system in ANSYS WorkBench 8.1
for reviewing results. How can I use a user defined coordinate system?


In order to get results in a non-global Cartesian coordinate system, follow the steps below:<br><br>1. Highlight Model and right click Insert > Coordinate Systems (this will...

My Workbench model has shell elements in it. Contact is used to connect shell parts together. However, I notice irregularities in the stresses at the contact interfaces (tremendous variations in stress values -- both hot spots and cold spots). What is wrong?


There is a known bug for edge-surface and surface-surface contact in WB when the underlying mesh on the target surface contains a mix of triangular and quadrilateral lower-order element faces. ...

For the input shown below, my stress results are zero. Why?


Defect 25209 was filed and subsequently corrected in the<br> UP20040628 build of ANSYS 9.0. The problem occurs for the<br> unique combination of SHELL181 KEYOPT(8)=2, real...

My plasticity analysis seems to get caught in an endless loop of repeated
bisections in which the new time increment is the same as before, thereby
repeating the exact same solution over and over. I am getting a message
about the incremental plastic strain computed in the iteration being larger
than the criterion, which then forces another bisection. There is also some
reference to re-specifying the criterion with the CUTCONTROL command.
What should I do to improve my convergence?


This "infinite bisection loop" scenario does not occur often, but we have seen<br> it occur when there is a singularity point from a load or boundary condition or<br>...

User does not see "Link to ANSYS APDL input" in Workbench Project Tasks. How does one gain access to ADPL input files?


User needs a DesignExplorer license to see "Link to ANSYS APDL input" under Project Tasks.<br>After adding a DesignExplorer license the user should be able to see this feature.

There is a new icon on the startup page in ANSYS Workbench 9.0 Preview 1
called "Multibody Dynamics Study." What is this new product?


ANSYS Development noted the following on July 2nd, 2004:<br><br> "The Workbench module for Multibody Dynamics is a work in progress. It will<br> not be publicly...

I get the following error whenever I try to solve a Workbench simulation:
"An error occurred when reading the xml results file(s). Please send the database to your Ansys support distributor."
What causes this error?


There could potentially be other causes for this message, but in this particular case, the error is due to the user having NO_ELDBW=1 set in his config81.ans file.<br><br>Workaround: ...

Q. In the ANSYS documentation, the help system states:

"Note: To import 2D and 3D region names into CFX-Pre, each such region must be defined with CMBLOCK commands when they are created in ANSYS."

But I didn't find that "cmblock" in ansys. Can you tell me more about where the CMBLOCK command is used?

A.

The named components that we referred to are not actually created with the CMBLOCK command. They are created in ANSYS using the CM command. E.g. CM,Inlete,ELEM, where "Inlete" is the name of the component. This will be what CFX-PRE sees.

Note that there is a bug in the initial release (fixed with the release of the first CFX-5.7 patch) where triangle faces are not read by CFX-PRE. The workaround for this is to use nodal components instead.

Here is some more information about CMBLOCK and the CDB file.

The ANSYS database is a binary file, and the ANSYS user desiring to use CFX will be creating 2D (for Boundary conditions) and 3D (for non-fluid regions) named components and writing them, along with the nodes and elements, to an ANSYS CDB file.

This ASCI version of the database is made by issuing CDWRITE. If you use the DB option on this command, the named components will be written to the CDB file. They are identified in the CDB file by a line with CMBLOCK. This line contains the named component name, what kind it is, and how many lines are to follow. The lines that follow for an element component would simply be element numbers in 8I10 format.

Now, what about the concept of a CMBLOCK "command"?

Well, it IS a command, but it is a command designed for use by the ANSYS CDREAD command. It was developed to speed up the reading of a CDB asci file so that the groups of lines could all be read in together rather than one at a time. So, in a way it is a "subcommand" of the CDREAD command.

An ANSYS user will never issue such a command. He/she would simply select the group of elements to be named and then name them something like


Q. In the ANSYS documentation, the help system states:<br><br>"Note: To import 2D and 3D region names into CFX-Pre, each such region must be defined with CMBLOCK commands when...

When I use "Advanced Meshing" module in Workbench (AI*Environment/ICEM CFD 5.0), I notice that only the "Nastran" solver is available.


This issue will be resolved in the first service pack of ICEM CFD/AI*Environment 5.0. In the meantime, the user can set the following environment variables for the system (Control Panel >...

QUESTION:

In HF analysis, the computation run time for 8.0 is much slower then 6.1 widely. Why does this happen and is there a workaround?


ANSWER:

We found 2 sources of the performance difference.
One is solver related; the other is related to element 120. I can tell you how to fix the solver issue and I'll
forward this information to the element developer for comment on the performance of el120.

After 6.1 we started optimizing memory usage for the solvers. The intent was to try and run problems
in memory ( incore ) rather than out-of-core whenever possible. Indeed, your 8.1 run was incore
while the 6.1 run ran out-of-core. But there is a gotcha with incore runs. ANSYS allows multiple loads with the same
factorization. To do this we save the sparse solver workspace so that on subsequent loads, as soon as we
determine that the boundary conditions are identical we can resume the sparse solver and just do
a forward/backward solve. This is much cheaper than doing 2 factorizations. For an out-of-core run the matrix
factor is already sitting in a file so all we have to save is the rest of the sparse solver work array. But, in
an incore run when we save the solver work array we end up saving the whole factor as well. The I/O
to do this is very slow on Windows. The way to avoid this is to use an undocumented option in the bcsopt command.
The tests that we ran using this option made a huge difference in solver time. Add this to your
input before the solve command:

bcsopt,,,,-1,,-5 - That's 4 commas, a -1 , and then 2 more and a -5. The -5 is there for performance
debug. The -1 surpresses writing that LN22 file for backup of the workspace.

Another way to get this done is to tell the solver to run in optimal out-of-core mode
rather than incore.. to do this use


bcsopt,,opti,,,,-5

I tried both solutions and got about the same results. Incore was faster but both were now
competitive with the 6.1 results. We also noticed that version


QUESTION:<br><br>In HF analysis, the computation run time for 8.0 is much slower then 6.1 widely. Why does this happen and is there a...

Do you have an example demonstrating eddy current and attendant joule heating calculations performed on a 3D model of an inductor? In my case, the inductor core is laminated and resembles a transformer with coil windings wrapped around the center leg of the core. Airgaps in the core produce fringing. The fringing drives flux normal to the laminations around the airgap, allowing significant eddy currents and joule heating to develop.


Attached is a parameterized input file that automatically creates a 1/8th symmetry model, performs a harmonic response analysis, and post processes for joule heating in the core. The input file...


Do you have an example of electromechanical coupling (bi-directional coupling between electrostatic field and forces and structural deformation) using the Multifield solver? In my application, voltage applied between the top and bottom surfaces of a hollow dielectric box produce structural deflection (much like that of a diaphram) in the top surface of the box.


<br>The attached presentation describes the model produced by the input file mdl12.inp. Electrostatic forces on applied to interior surfaces of the box across interface #1. Structural...

A user of the Workbench CATIA v5 reader receives a plug-in error when reading in a known good part.
The user reboots the computer, then the same part reads into Workbench OK.
This seems to work for a while, then the attach begins to fail again. The user must reboot the computer in order to get it to work again.


This problem occurs on computers where the CATIA v5 CAD program is installed in addition to Workbench.<br> It is caused by a conflict in the Windows environment path when a CATIA part is...

In Workbench Simulation - Reaction forces often do not match the applied loads. The documentation contains the following note about this, but what is the root cause?

Note (from Workbench Documentation)
A reported reaction may be inappropriate if that support shares a surface, edge, or vertex with another support, contact pair, or load. This is because the underlying finite element model will have both loads and supports applied to the same nodes.

If a model contains two or more supports that share an edge or vertex, use caution in evaluating the listed reaction forces at those supports. Calculation of reaction forces includes the force acting along bounding edges and vertices. When supports share edges or vertices the global summation of forces may not appear to balance. Reaction forces may be incorrect if they share an edge or surface with a contact region.


This can happen for several reasons. Most obvious is when you have different boundary conditions sharing the same nodes. In ANSYS, each constrained node has a reaction force. Consider the case...

How do you remove the ANSYS Version bitmap from Workbench Window:


To remove the background "ANSYS Workbench 8.1" image from the upper right-hand corner of the graphics area, remove this file: C:Program FilesAnsys...

Are there any examples showing how to reorient the element coordinate systems of a
SOLID46 model with the EORIENT command and output the interlaminar shear stresses?


Yes, please see the ANSYS 8.1 example below.<br><br><br><br>fini<br>/clear<br><br>/title, SOLID46 Laminate Orientation...

Workbench runs correctly the first time, However each time thereafer, an Internet Explorer Script Error referencing StartScreen.htm occurs.

Dialog: Internet Explorer Script Error
Line 37
Char 2
URL: file: C:Program FilesAnsys IncAISOLStartPagestartPagesLanguageen-usStartScreen.htm
Do you wish to continue running scripts on this page?


This problem may be caused by Multi-byte/Unicode characters in the Windows username:<br> This has been observed when Korean characters are in the username:<br> Example : ...

In SHELL181 element with multiple layers, how does the temperature vary through the thickness?


In ANSYS Release 8.1, the temperature is assumed to vary linearly through each layer. For example consider an element with 2 layers with a temperature of 0 F specified for the bottom of the...

In a Spectrum analysis with multiple solves, how are the results combined?


In ANSYS Release 8.1, by default, the SRSS command combines the results from each load case.

I noticed that, in my beam model, I get different stress results if I add plasticity, even though yielding has not occurred. Why does adding a plasticity model to BEAM188/189 change the stress results?


Please refer to the last statement in the 8.1 Theory Reference for BEAM189 (Section 14.189.2):<br>¿If the material is elastic, stresses and strains are available after extrapolation...