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When we install ANSYS on a 32-bit computer, the STEP format is already checked under Parasolid Geometry Interface. However when we install ANSYS on a 64-bit Windows computer, there is no way to check STEP format. As a result, we can not import STEP file into ANSYS DesignModeler in a 64-bit computer, which has no problem in a 32-bit computer. Do you have any suggestions?


STEP is not supported on 64-bit systems, so we can not support it with 64-bit WB 11.0.<br><br>You would need to import the geometry and save the .agdb file on the 32-bit machine and...

I defined two Named Selections in DesignModeler, which are two sides of an interface/contact between two bodies. I then group these two bodies into one part. When I transfer this geometry into meshing under Workbench, I cannot see both of my Named Selections. After meshed the geometry, I cannot use these two Named Selections in pre either.


This is the designed behavior, although a future release may change it. It is because your Named Selections are in Regions of Shared Topology.<br><br>Note that your named selection may...

VM248 uses interface elements (INTER*) with a cohesive zone material model (TB,CZM) with an exponential material behavior (TBOPT=EXPO). The interface properties are listed as follows:

C1 is given in "MPa" units
C2 is given in "mm" units
C3 is given in "MPa" units

The theory reference for the CZM material model shows that this material is defined with maximum stress (C1 = sigma_max), normal separation (C2 = delta_n), and shear separation (C3 = delta_t). What are the correct units for C3?


C3 should be in units of length. This was reported in documentation defect 61955 and will be corrected for 12.0.

I would like to write results only for specific load steps. The "OUTRES" command allows me to set up a result writing frequency, but I need individual control.


You can issue the "OUTRES" command each load step to achieve this effect. The input file below sets up a simple 4-load step analysis and requests results only for load steps 2 and...

I am solving a transient thermal driven cavity problem. However, I see that mass is not conserved even though there are no inlets and outlets. Why is this?


We have an initial mass corresponding to the pressure and temperature. The temperature boundary conditions then throw heat into and out of the system at the walls as the transient develops. ...

In melting or solidification case, sometimes the termperature field can go a little bit unphysical, how to fix it?


In meling or solidification case, users have to define source term to dampen the momentum and turbulence equation when there is solid or solid forms, this sometimes can cause the temperature to go...

I am trying to run a modal and/or linear buckling analysis, and my model contains point masses. It takes a very large amount of memory to solve, or I get an insufficient memory available error. Why is this, and what can I do to fix it?


ANSYS needs a large amount of memory for point masses because they are created internally using multipoint constraints. This creates a very dense mass matrix, which requires tons of memory. In...

I tried to set the number of integration layers to 1 in the SHELL131 element (parameter NUMPT). An error message referring to inadequate storage resulted, and it told me to set the value to the default of 3. This does not appear to make sense. What should I do?


The NUMPT parameter should not be set at all for SHELL131 elements, and although it should be ignored by ANSYS, it is not. As a workaround, leave the parameter blank.

I followed the basic routine to create geometry and mesh. After modifying the geometry slightly, how can I use the previous mesh controls settings to create the mesh for the new geometry and still keep the files for the original project?


To use the previous mesh control settings for the slightly-modified geometry and still keep the files for the original project, you can do the following:<br>(1) Create the original...



In the context of CFX user Fortran, how can I call C or C++ functions from Fortran routines?


<br><br>There quite a few issues to watch out for, which may or may not be relevent, depending on exactly what you are doing. Most apply to calling C or C++ functions from any Fortan...


I have installed ICEM CFD 11 SP1 on my Windows Vista 64-bit platform. I am unable to get ICEM CFD 11 to launch - I get a pop-up message:

ANSYS110_DIR doesn't point to a readable directory

I have checked and the ANSYS110_DIR environment variable seems to be set correctly


<br>This is a known problem on Windows Vista. You need to edit the file c:program filesansys incv110icemcfdwin64_amdbinicemcfd.bat and replace the line<br><br>if not exist...



I have a solver error when using a flamelet library:

Parameter "Laminar Burning Velocity" has been assigned an expression containing an unavailable variable: T

In CFX10, I was using a Laminar Burning Velocity which depends on T. It does not work with CFX11?


<br><br>Laminar burning velocity should not depend on the local temperature ¿T¿, because local T changes across the flame front and is based on unburned state on one side...

How does ANSYS calculate the shear correction factor for BEAM188/9 elements?


Formulas for shear correction factor are found in the following references:<br>¿ Schramm, U., Kitis, L., Kang, W., and Pilkey, W.D., "On the Shear Deformation Coefficient in...

Is there a way to specify which license ICEM checks out first?
Example:
A customer has both academic teaching and academic research licenses on the university server.
If the sudents open ICEM first, the research licenses are checked out.
Just if all research licenses are used, the teaching licenses are used.
Is there a way to tell ICEM that the teaching licenses should be used first?


No, there is no such option in ICEM CFD stand alone. You can not specify which license to start with first.<br>However, when the license is set by Workbench, then Advanced Meshing will use that.

I would like to be able to borrow licenses for my laptop from the license server so that I can work with the CFX software when I am not connected to the license server. Can I do this? We have a 5 task Academic Research license.


The BORROW option is only available for the Academic Teaching licenses. You have an Academic Research license so unfortunately you won't be able to make use of this option.

Is it possible to change units during a DesignModeler session?


No, once you have chosen a length unit at the start of a DesignModeler session, you cannot change these units later in the session.<br><br>However, there may be possibilities whilst...

How can I find the maxima of a variable and the position of the maxima in CFX Post?


To find the maxima of a variable in CFX-Post:<br><br>1. From the top menu Insert, select Location and then Point<br>This will create a locator eg Point 1<br><br>2. In...

Is it possible to import Gambit mesh files into CFX-Pre?


Gambit files (both .cas and .msh) files can be imported into the latest version of CFX-Pre 11.0 SP1. This includes the import of 2D meshes.

CFX-Post opens but when when it askes me if I want to load the domains and I click yes - it crashes.
The error message is that it is "Aborting due to unknown exception"
(stack trace failed)


<br>1. This error can occur if the preferences file (which CFX-Post reads from and writes to upon startup) becomes corrupted for any reason. The solution is to delete the preferences folder...

Why is ANSYS sometimes adding DOF constraints automatically when using Sparse solver and small deflection?

NOTE: ANSYS issues the following warning in the output:

*** WARNING *** CP = 4.969 TIME= 08:45:58
Small equation solver pivot term encountered at UY DOF of node 2.
ANSYS automatically constrained this DOF. Check for an insufficiently
constrained model.

With PCG solver, ANSYS crashes with:

! *** FATAL *** CP = 2.297 TIME= 10:
! Negative or Zero pivot; Pivot Value = 0.000000e+000.


We add the constraint to prevent rigid body motion. We are constraining the DOF that gave us the small pivot term (UY DOF of node 2 in this case). It is an appropriate stabilizing constraint in...

SYMPTOM:
It is not possible to set a value for the Minimum Impact Angle which may be used at walls in particle transport calculations.

PROBLEM:
The units of Minimum Impact Angle are not set in the RULES file.


WORKAROUND:<br>Edit the RULES file and add the missing units of [deg] to the default value and lower bound of the parameter 'Minimum Impact Angle'.<br><br>FIXED IN:<br>ANSYS CFX Release...

Class 3 Error

SYMPTOM:
The 'Heat Flux' variable, written in the res file, and plottable in CFX-Post is incorrect at Fluid-Fluid GGI interfaces. However, the flows reported in the out file and in the Solver Manager are correct.

PROBLEM:
The CFX Solver should not be writing this


WORKAROUND:<br>No workaround is available.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0. A custom executable for ANSYS CFX Release 11.0 SP1 is available on...

**** Entered By: jjdoyle @ 11/15/2007 03:04 PM ****

Q. How do we get "Contact Tool" => "Initial Information" to solve in Simulation when hyperelastic material is present?

A. When hyperelastic material is defined in the model, the solution will only work when large deflection is activated. Unfortunately, turning this on in the "Analysis Settings" folder is not going to work for the partial solve being done in the Connections Branch.

You have to add a command object before the Connections Folder with the following command script included:

/SOLU
NLGEOM,ON
/PREP7


**** Entered By: jjdoyle @ 11/15/2007 03:04 PM ****<br><br>Q. How do we get "Contact Tool" => "Initial Information" to solve in Simulation when...

**** Entered By: jjdoyle @ 11/15/2007 05:05 PM ****

Q. User set-up an anisotropic elastic material table on Version 10/11 using:

TB,ANEL,3,2,,0
TBTEMP,70
TBDATA,1, x,x,x,x,x,x
TBDATA,7, x,x,x,x,x,x
TBDATA,13, x,x,x,x,x,x
TBDATA,19, x,x,x,x,x,x
TBTEMP,200
TBDATA,1, x,x,x,x,x,x
TBDATA,7, x,x,x,x,x,x
TBDATA,13, x,x,x,x,x,x
TBDATA,19, x,x,x,x,x,x

It appears that the input was reflected/repeated correctly in the output. TBLIST,ALL,ALL resulted in a columnar listing format which correctly repeated the input, but the output for (stiffness matrix at temperature) in a matrix format correctly repeated only the first temp set and the temp and stiffness constant values were zero for the second temp set.


A. This was a defect (#58517) that has been corrected for 12.0. This is only a listing error (caused by a subscript error in tbAnelLis.F) TB,ANEL is implemented correctly within the 10.0/11.0 code.


**** Entered By: jjdoyle @ 11/15/2007 05:05 PM ****<br><br>Q. User set-up an anisotropic elastic material table on Version 10/11...

SYMPTOM:
CFX-Pre crashes on start-up, perhaps even logging the computer off. One machine set-up this has been seen for is:

Dual Core Xeon Proc 5160 3.00GHz, 4MB L2 Cache, 1333MHz
Red Hat Enterprise Linux WS v4 Intel EM64T 64bit
16GB, DDR2 ECC SDRAM
nVidia,Quadro FX 3500, 256MB PCIe x16


PROBLEM:
The cause of the problem is likely to be an unsupported graphics card.


WORKAROUND:<br>No workaround is available.<br><br>FIXED IN:<br>No fix is available.