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The ANSYS documentation for the *GET command says this: "*GET command operations, along with the associated Get functions return values in the active coordinate system unless stated otherwise." I interpret this "active coordinate system" to be CSYS, but a simple test shows that some values are retrieved in RSYS, the result coordinate system. What is going on?

There are two "active" coordinate systems in ANSYS: one for geometry (CSYS) and one for results (RSYS). Which coordinate system is "active" depends on what type of data...

I am doing a transient rotor stator calculation with a rotating and stationary component which rotates about the global z-axis. I set up monitor points for the x- and y-components of the force, but they do not behave as I would expect. For example, when the blade is parallel to the x-axis, most of the force should be in y-direction, whereas most of the force should be in the x-direction whenthe blade is perpendicular to the x-axis. I don't see this type of change, however, as the x-component forces oscillates slightly abouta non-zero value as the simulation proceeds. The force components that I calculate in Post are different from the solver monitor valuesand do behave as I would expect. What causes this behavior?

<br><br>In a transient rotor stator calculation, the rotating frame mesh is not really rotated during the simulation, as all meshes (stationary and rotating frames)<br>retain...

I have transferred my model from Simulation into ANSYS, and now I want to list or graph my loads or boundary conditions to verify that they were applied correctly. How can I do this?

Simulation sets up loads and boundary conditions using tables, so retrieving this information requires a couple of steps.<br><br>(1) make sure you are in /PREP7<br><br>(2)...

Class 3 ErrorSYMPTOM:If the direct intersection method is being used in the creation of GGI interfaces, which is a beta feature of CFX 11.0 enabled by the expert parameter setting 'ggi intersection algorithm = 2', then if the code for GGI creation runs out of memory, the calculated interface will be in error, with wrong values of non-overlap. This is most likely to occur when there are a large number of control surfaces and only a small amount of memory, which occurs in the partitioner.PROBLEM:This is due to the solver not stopping when it runs o

WORKAROUND:<br>Set additional memory for parallel runs using the direct intersection method.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0. A custom executable for ANSYS CFX...

Class 3 ErrorSYMPTOM:If a single-precision transient case with a large number of Lagrangian particles (approx. 10,000 or greater) is restarted in double-precision, then the restart may fail with a segmentation violation or other error, or the results may be incorrect.PROBLEM:The solver code contains an uninitialised variable in such a case and this may lead to a memory overwrite. This is most likely to cause the solver to stop with an error, but has the potential to cause incorrect results to b

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

I need to calculate the "GRMS" values in a Random Vibration analysis, but I see no reference to "GRMS" anywhere in ANSYS.

The RMS values are known as "one-sigma" values in ANSYS. Since "G" refers to acceleration in terms of gravitational acceleration, then "GRMS" is the...

When using ANSYS ICEM CFD to generate a tet/prism mesh, how is it possible to create a mesh with different parts on each side of an internal wall?

<br><br>Note that enabling the 'split' option for the internal wall in the 'Mesh size for parts' form is NOT the answer. This results in the same part on...

Setting boundary, source, etc. values as non-trivial functions of time.

Sometimes the need arises to switch a quantity such as a boundary or source value on, off or between discrete values at certain times during the course of a transient run. Or, quantities may need...

Class 3 ErrorSYMPTOM:A velocity excitation can be specified as part of the mass and momentum specification for a velocity-specified non-reflective inlet. However, this appears to have no effect if the velocity excitation is specified in cylindrical coordinates.(Note that non-reflective inlets are a beta feature and so not enabled in CFX-Pre by default.)PROBLEM:A coding bug means that if the velocity excitation is specified in cylindrical coordinates, it is ignored (

WORKAROUND:<br>Specify the velocity excitation in Cartesian coordinates.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

Class 3 ErrorSYMPTOM:A case using the transition model may give incorrect results and may incorrectly predict the transition location.PROBLEM:There is a coding error in the calculation of F_length (the length of the transition zone) as a function of the transition onset Reynolds number Re_theta_t, for values of Re_theta_t in the range of approximately 600 and 1200 (see the attached plot). This is expected to have little impact on mo

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

SYMPTOM:It is possible to get a floating point error carrying out multiphase flows, when there is a single continuous phase which is a compressible variable composition mixture.PROBLEM:This is due an uniinitialized variable in the procedure for converting between static pressure and total pressure. Even if the case does not fail, convergence is likely to be adversely affected.

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

Class 3 ErrorSYMPTOM:When a mass flow calculation is performed on a boundary in CFX Post using the Function Calculator, the result is sometimes of the wrong sign.PROBLEM:This is due to an error in the approximate mass flow calculation algorithm in CFX Post. The approximation is invoked when CFX Post does not find specific integration point mass flow data sets in the results file of interest. The data sets are not present in: - Selected Variable transient results files - Selected Variable backup filesThe data sets are always present in Final results files, Standard transient results files and Standard

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

Class 3 ErrorSYMPTOM:When using the Function Calculator in CFX Post to perform mass flow calculations on boundaries in a transient calculation, the intermediate results are significantly different to those reported by the solver (e.g. on Monitor Points). PROBLEM:This is due to a bug in the CFX Solver which prevents integration point mass flow data, used by CFX Post for accurate mass flow calculations, being written to intermediate (Selected Variable) results files. These data should be written when the option 'Ouput Boundary Flows' is enabled for the results files, but

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

Restarting transient-thermal cases in Simulation is not possible with the v11 Simulation interface. How can the restart be accomplished with Command Objects?

It is possible with the following steps:<br><br>(1) Three Simulation settings under the details of "Analysis Settings" are necessary for the initial run: the ANSYS...

I have installed the ANSYS License Manager on my Windows Vista platform but the License Manager will not start when I select Start the License Manager on the ANSLIC_ADMIN utility. I get an error: Error occurred: Access is denied.

<br>Go to the Control Panel and select User Accounts.<br><br>If User Access Control is switched on you will need to switch it off to start the License Manager. When the License...

Is it possible to use DesignXplorer with APDL and specify multiple processors and/or distributed ANSYS?

First, DX with APDL does not use Simulation Solve Process Settings or Remote Solution Manager settings.<br><br>Generally, this method is for third-party solvers, but the same principle...

How do I create an aerofoil cfd model from a points file in DesignModeler?

<br>The procedure for generating geometry for an aerofoil is as follows:<br><br>1. The points data file needs to be broken into 3 or more groups to reflect the different curves...

Class 3 ErrorSYMPTOM:In a multiphase flow, using an expression involving a flow variable in any section of a setup that is fluid specific will cause the variable to be implicitly prefixed by the fluid name. For example, in a two-phase flow with Air and Water, if a user uses the variable 'Density' in an expression, they may very well expect that the density of the fluid mixture will be used, as it would be in some contexts, but CFX would actually implicitly use the density of air or water in fluid specific contexts including boundary conditions, sources etc. There is in fact no way to refer to the mixture density in these contexts. This overall problem also applies to multicomponent flows and sections of the setup that are component specific. PROBLEM:This behaviour of the code is actually by design, and is useful sometimes if one is aware of it. However, the documentation is not at all clear on this, so for a significant proportion of cases, users are likely to get code behaviour and results that they d

WORKAROUND:<br>No workaround is currently available.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

I notice that the 3rd principal stress is always zero in tension for SHELL181, SHELL43, and SHELL63 elements. This is not consistent with an analysis done in NASTRAN using shell elements. NASTRAN reports identical results with ANSYS for SEQV, S1, and S2, but S3 is truncated to zero in tension. Is this a bug or code limitation in ANSYS?

This is not a bug. The shell element is in a state of plane stress, so when ANSYS reports principal stresses, there will be one which is expected to be, and is, zero.<br><br>The three...

Are there any SOLSH190 examples of analyzing a composite structure with debonding via Cohesive Zone Material (CZM) delamination?

Yes, please see the attached ANSYS 11.0 SP1 example showing the debonding of a composite channel beam structure using the contact element option of CZM. Both a temperature load and a concentrated...

Class 3 ErrorSYMPTOM:When using some of the secondary break-up models. specifically the TAB, ETAB, CAB and Schmehl models, dynamic drag factor correlations are used to calculate the drag on particles, and any drag specified by the user, eben through CEL, is ignored.PROBLEM:This is an intended part of the design of these models, but neither the product, e.g. CFX-Pre messages or the CFX Solver out file, nor the documentation informs the user clearly enough that this

WORKAROUND:<br>Use the expert parameter setting 'pt dynamic drag model = 1'.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0.

I am having problems starting the ANSYS License Manager version 11 on my Windows Vista 64-bit license server. When I start the ANSYS License Manager (ANSLIC_ADMIN Utility) and select the option Start the License Manager I get the following error message:=====================Error occurred: The service did not respond to the start or control request in a timely fashion.=====================

<br> The license manager daemons (lmgrd and ansyslmd) were upgraded at version 11 SP1 to FLEXlm version 10.8.5. You must use the version 11 SP1 license manager on a Windows Vista platform....

Does the Workbench 11.0 SP1 plugin provide support for Pro/ENGINEER Wildfire 4.0 ?

Informal testing and feedback from customers indicate that the Pro/E plugin released<br> with Workbench 11.0SP1 will work with Pro/ENGINEER Wildfire 4.0, exceptions as...

I am trying to introduce friction in one of my body-to-body joints in Simulation 11.0 using a command object with the following commands: TB,JOIN,_jid, , ,FRIC TBDATA,06,1e15 TBDATA,11,1e15 The problem is that it has no effect. What is wrong?

The FRIC sub-option on the TB command specifies the stick-stiffness for the hysteretic friction in joints. It is to be used in conjunction with JNSA or JNSx(x=1,6). If the JNS suboptions are not...

I have an array in a text file, and I need to read it into ANSYS. The array is written out in another analysis, and can change length depending on a number of parameters. I can use *VREAD to get the array data, but the *VREAD requires that the array is previously defined, and I do not know in advance how many points will be in the text file. What can I do?

If your array data always has the same number of columns, and you only need to know the rows, you can use the /INQUIRE command.<br><br>/INQUIRE, Parameter, FUNC, Fname,...