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Class 3 Error

SYMPTOM:
The average value of the magnitude of a vector variable is wrongly computed by CFX-solver.

PROBLEM:
The average of a vector is computed in the CFX Solver as:

average(vector)= ((ave(component_1)@location)^2 + (ave(component_2)@location)^2 + (ave(component_3)@location)^2 + ...++ (ave(component_n)@location)^2)^0.5

instead of:

average(vector) = ave(((component_1)@location)^2+(component_2)@location)^2 + ..+(component_n)@loca


WORKAROUND:<br>Use an additional variable to define the magnitude of the vector. Then, calculate the average value of the additional variable.<br><br>FIXED IN:<br>ANSYS CFX Release...

I am doing a mode-superposition harmonic analysis in Workbench Simulation, and I am using a command object in the Environment branch to modify some settings. I discovered that the command object is executed twice during the solution (once for the required modal and once for the harmonic).


You can use a combination of *GET and *IF commands to control which solve certain commands get executed for. Please see the following example below:<br><br><br>! command object...

Trying to start the license manager on a linux machine, the customer receives the following in the license.log file:

14:50:26 (ansyslmd) Vendor daemon can't talk to lmgrd (Cannot connect to license server system. (-15,570:115 "Operation now in progress"))
14:50:26 (ansyslmd) EXITING DUE TO SIGNAL 37
14:50:26 ((lmgrd)) Loop info: MT:5 VD_HB:0 reset:0clients:0fd's:0
14:50:26 (lmgrd) ansyslmd exited with status 37 (Communications error)
14:50:26 (lmgrd) Since this is an unknown status, license server
14:50:26 (lmgrd) manager (lmgrd) will attempt to re-start the vendor daemon.

What causes this?


In this case, the customer's /etc/hosts file did not contain the correct information.<br>Make sure that it lists:<br><br>127.0.0.1 localhost<br>###.###.###.### ...

Class 3 Error

SYMPTOM:
Using a global range on a plot showing "Total Mesh Displacement" in CFX-Post shows correct results. However, if one of the components of Total Mesh Displacement is plotted instead (e.g. "Total Mesh Displacement X") on a transient run, then the global range shown is actually only the range for the last timestep, rather than the range for all timesteps. This can be misleading because this incorrect global range does not update if the timestep is changed, and it may not be clear that the range has been truncated.

For example, if Total Mesh Displacement X varies between 0 and 5 [m] on timestep 3, and varies between 0 and 3 [m] on the last timestep, then the global range will be shown in CFX-Post as 0 to 3 [m] rather than 0 to 5 [m]. If you change timestep to timestep 3, the global range will remain set to 0 to 3 [m], and any part of the plot where Total Mesh Displacement X takes a value above 3 [m] will be coloured as if it has a value of 3 [m].

A similar problem exists for components of any other vector variable (such as Velocity or any gradient vector), but only if Conservative boundary data is used for the plot. Since Hybrid boundary data is plotted by default, this will be seen less commonly. (Note that for Total Mesh Displacement the problem applies to both Conservative and Hybrid value plots.)

PROBLEM:
The CFX-Solver is not recording the correct global ranges for conservative values of any vector quantity. Total Mesh Displacement does not have any Hybrid data, so the Conservative data is used for all plots of t


WORKAROUND:<br>Avoid using the Global range for any affected plot of a vector component, by using a Local range or User Specified range instead.<br><br>FIXED IN:<br>ANSYS CFX Release...


How can I visualize the temperature gradient in ANSYS CFX?


<br>The gradient of temperature is not a standard variable but it can be represented by a vector Additional Variable (AV) which is created in CFX-Pre. The components of the AV are defined as...

I created a multi-body part using shell bodies in DM. In the "Shared Topology Method" field I indicated "Edge Joints". When I take this model into Simulation there doesn't appear to be any joints and the mesh is discontinuous. What's wrong?


The "Edge Joint" option indicates that you wish to employ user defined (manual) edge joints. In some cases users don't want all edges to have joints so this option is for...

I am trying to retrieve nodal results using JScript. I can call the nodal result values of a 3D model using

DS.Tree.Projects(1).Models(1).Environments(1).AnswerSet.StructuralResults.Arrays(1).Value(1);

but this doesn't work for 2D plates or 3D shells. Is there another method for accessing these values?


As of v11, these values are only being populated for solids, not plates or shells.

When will Team Center Engineering be supported on Windows XP x64?


TCE 2005 support has been added into version 12.0. We are currently looking into TCE 2007 support for the near future.

How can I assign cross sections to line bodies using JScript in DM?


Please see the attached zip files for examples.

Can I use a cylindrical coordinate system for applying displacements? Is this planned for release any time soon?


The nodal coordinate system remains Cartesian, regardless of which system it was initially aligned with. Applying a radial displacement would likely yield the desired results, but a...


Is there a good way to identify turbulence structures in a flow?


<br>One way to do this is by plotting isosurfaces of low pressure as well as isosurfaces of the so called Q criterion.<br>The attached document describes of Q is defined and how it can...

How are rotational velocities calculated for multiple rotors in rotordynamics?


Even when there is only one rotor, the rotational velocity input using CMOMEGA is used only to determine the direction, not the magnitude. When there are two rotors, and the input looks something...

I'm writing a script to automate my analysis. I can save an image of the graphics section of the window, but I want to take a screenshot of the whole Workbench window. Can I do this?


Not directly using the Workbnech API, but some applications (e.g., IrfanView) supports taking screenshots from the command-line. Then, you can call it using...



In a 1:1 mesh interface, which is explicitely set to GGI in CFX Pre, there are non-overlap fractions. This can be visualized in CFX Post. The non-overlap fractions appear especially in regions where the interface is highly curved.
How can this be explained? How to avoid this?


<br><br>The GGI intersection algorithm seeks for overlapping cells from the corresponding interface partner side within a certain tolerance. Thus, in highly bended parts of the mesh,...

Class 3 Error

SYMPTOM:
When heating a Homogeneous Binary Mixture containing a liquid and gas phase, and where the gas phase Specific Heat Capacity is defined in NASA polynomial format, the temperature of the mixture is correct as long as some liquid is present. However, when all the liquid has evaporated the addition of more heat does not increase the temperature of the vapour.

PROBLEM:
This is due to a bug i


WORKAROUND:<br>Re-formulate the NASA material Specific Heat Capacity in terms of CEL expressions.<br><br>FIXED IN:<br>ANSYS CFX Release 12.0. A custom executable for ANSYS...

The user is trying to do load case combinations with SHELL63 results and KEYOPT(11)=2. He claims that he can calculate the square of top surface or bottom surface using load case combinations, but when he tried to do this with the MID Surf results he gets the average of top and bottom not the square.


This is a class 3 error that has been corrected at 12.0. See Defect Report 66201. It effects element types SHELL63 with KEYOPT(11)=2 and SHELL93, 181 and 281 with KEYOPT(8)=2. The error has been...

I am running an ANSYS 11.0 contact analysis with plasticity on a LINUX 64-bit machine and am getting the error "oops - nrow, ncol, lpan, lpanel = ..." (see below). Why ??? I have been told that the undocumented command options: BCSOPT,,OPTI and EQSLV,SPARSE,1.0e-5,-1 may help, but EQSLV,,TOLER is not documented for the sparse solver and BCSOPT,,OPTI is not documented at all. What do these options mean?

*** WARNING *** CP = 53790.602 TIME= 09:59:25
There are 10 small equation solver pivot terms.
EQUIL ITER 2 COMPLETED. NEW TRIANG MATRIX. MAX DOF INC= -0.1695E-03
LINE SEARCH PARAMETER = 1.000 SCALED MAX DOF INC = -0.1695E-03
6 CONTACT POINTS HAVE CHANGE OF CONTACT STATUS
FORCE CONVERGENCE VALUE = 21.79 CRITERION= 8.572
MOMENT CONVERGENCE VALUE = 0.3063E-07 CRITERION= 0.5312E-04 <<< CONVERGED

*** WARNING *** CP = 53843.523 TIME= 10:01:02
The calculated reference MOMENT CONVERGENCE VALUE = 1.367118957E-08 is less than 1E-2 a threshold zero, A value of 1E-2 or specified MINREFis used. Check results carefully.

oops - nrow, ncol, lpan, lpanel = 9815 58724039642440396423


Development noted that BCSOPT,,OPTI is documented in 12.0 and commented on the error:<br><br>This is an internal error message from the original Boeing sparse solver code (not added by...

Is there any detailed information available concerning the RESP command?


Yes, please see the discussion below for analyses conducted in ANSYS 11.0 SP1 and also refer to Solution 335519 "Question on generating response spectrum in ANSYS 8.1 from array...

How do I get the SESAME Library and Convert it to AUTODYN Material Library?


The SESAME library was collected and edited by Los Alamos National Laboratory in USA. SESAME library is a data collection of equation of state for about 70 materials including metals, minerals,...

When importing a simple IGES file in ANSYS 11.0 sp1, with the option 'defeature model,' a memory error occurs on 32-bit windows systems. Normal default import does work. On a 64bit Windows the import of the IGES file, no error appears but cannot use NUMMRG.
--------------------------------------------------------------
*** FATAL *** CP = 2.262 TIME= 12:20:29
This model requires more scratch space than available. ANSYS has
currently allocated 410 MB and was not able to allocate enough
additional memory in order to proceed. Please increase the virtual
memory on your system and/or increase the work space memory and rerun
ANSYS. Problem terminated.


This behavior of de-featuring IGES running out of memory on 32-bit Windows PCs was reported as defect 43168 during development of ANSYS Release 11.0. It was determined that it is not...

I a need to execute a DOS command from within Simulation. What are my options?


You can use the "Tools" > "Run Macro" and call an application from JScript:<br><br>//**********<br>var command =...

When I do a prestressed modal analysis with frictionless contact between parts, the closed contact is not recognized in the modal run. Frequencies and mode shapes are calculated as if there were no contact, even though the contact status is closed at the end of the static structural analysis. Also, there is nothing in the documentation on how a modal interprets the frictionless contact status in a prestress modal run.


This is a defect at 11.0SP1 (#67727). The workaround is to add in a command object with "EMATWRITE,YES".

I have a hollow pipe, and I want to apply a torque load to it. How are moments applied in Simulation?


Simulation creates a node at the center of the selection, and attaches the nodes on the surface to a pilot node using rigid or deformable contact. It then applies the moment to that pilot...

Is it possible to change the number format in the FE-Modeler output? For example, a NASTRAN node is defined like this:

GRID,1,,3.184385970E+001,3.175000000E+000,9.616215154E+000

where each coordinate value is described in an (F20.9) format. Can I change that to something else like (F25.20)?


At this time, the number format is hardcoded into FE modeler.

When I run my JScript macro in DesignModeler 11, I get an error at the line where I use "agc.Frozen". It worked in v10. What has changed?


The "agb.LinePt()" object attribute named "Material" was changed to "Operation." To fix your script, simply change the...