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MEDI April 6, 2010 05:33

CFX-Mesh Error
 
1 Attachment(s)
Hi everyone
I have a problem .
I use ansys workbench 12 to create a free surface flow around solid obstacls.
I created 3D-files by Design-Modeller.
I created CFX-Mesh file and imported 3D into it.
After setted 2D-region and change "default body spacing"(maximum 0.3mm)
I try to preview the volume mesh but I cann't
The error message said : " Failed to carry out requested action "
in the details Message : Internal Error" MEM_EXTD Storage allocation failed
Number of words requested -->61680016.
Array --> adt

What should I do?
Thanks in advance

ghorrocks April 6, 2010 18:35

Looks like you ran out of memory. Some options include: Move to a machine with more memory, Move to a 64 bit machine, use a coarser mesh, use another meshing application (eg ICEM will probably be able to do it no problem), mesh the geometry in smaller pieces and join them up with interfaces, .... and many more options if you have the imagination.

longbow April 7, 2010 12:40

You should use "Extrude 2D Mesh" option to create a 3D mesh which has only one cell in Y-direction.

MEDI April 8, 2010 09:18

thank you very much,
Finally it was a memory problem.
but now after generating the volume mesh, I can not transfer it to CFX-Pre ,The error message said "An upstream mesh was not available, it will not be updated in CFX-Pre
please help me.

MEDI April 8, 2010 09:38

1 Attachment(s)
this is problem's pic

jbritton April 8, 2010 12:28

This sounds like a problem I have had when I havn't saved the project in workbench before I generate and save the mesh.

To get round this I usually have to go back to the geometry, create a plane anywhere and then save it,and the project, then regenerate the mesh and now you should be able to open it in pre.

Hope that helps

ghorrocks April 8, 2010 18:15

For a geometry like this you should use the extruded mesh as longbow suggested rather than a tet mesh. Not only will it generate a better quality mesh but it will also use a lot less memory.

MEDI April 9, 2010 13:34

You're right jbritton
I'm sorry but I have yet another problem
When I run CFX Solver Manager 12.0
i get the following error message :

-----------------------------------------------------------

If the isolated regions do not have the pressure level set either by the boundary conditions or using a reference pressure equation, you may encounter severe robustness problems.

This situation may have arisen because a domain interface was not properly defined during problem setup. Please carefully check the setup.

The solver will stop now and write a results file. The isolated regions can be visualised in CFX Post by making plots of the variable "Isolated Volumes".

If you are sure that the pressure level is set in each isolated fluid region then you can force the solver to turn off this check by setting the expert parameter "check isolated regions = f".

+--------------------------------------------------------------------+ | An error has occurred in cfx5solve: | | | | The ANSYS CFX solver exited with return code 1. | +--------------------------------------------------------------------+

End of solution stage.

+--------------------------------------------------------------------+ | An error has occurred in cfx5solve: | | | | ANSYS Solver terminated with return code 3840 | +--------------------------------------------------------------------


What is the isolated areas in my problem, and what's pressure level ?
Where I should put it ?

help me out plzzz i am stuck

longbow April 9, 2010 13:57

Have you tried to located isolated regions as explained in error message: The isolated regions can be visualised in CFX Post by making plots of the variable "Isolated Volumes"? Once you know where it is, you may have an idea how to solve it.

MEDI April 10, 2010 06:03

If I guess I know the isolated regions in my model, how should their I impose the pressure level ?:confused:

ghorrocks April 10, 2010 06:28

No, the point is you probably don't want the isolated mesh regions. If they exist you want to fix them and eliminate them.

MEDI April 12, 2010 01:14

I'm stuck.:confused:
I can not find these isolated regions, is there someone can tell me how I can view them, so I can delete them.
help me please.:(

artemis64s August 4, 2010 09:30

Mesh Error- CFX
 
Hi guys
I have the same error in my CFX problem.
can anyone help me in that?


Internal error:
'' MEM_EXTD storage allocation failed
number of words requested = 9204897
Array = xyz ''
Warning :
'' problem: CAD model contained faces with small angles.
result : surface mesh quality may be poor in this region, particularly if the mesh spacing is small.
Cause: CAD eges almost tangent to CAD vertex.
Action: If a fine mesh is needed in this region, rebuilt the CAD model to remove the small angle. ''


I am not that much expert in CAD. Is there any possibility to remove these errors without correcting the CAD model?


Thanks in advanced.

ghorrocks August 4, 2010 19:06

This message is nothing about isolated mesh regions. It is saying your mesh quality is poor and it could not mesh it. Do some meshing tutorials to help you learn about meshing difficult objects.

artemis64s August 5, 2010 05:52

OK, Thanks, I will go for that..

artemis64s August 5, 2010 08:20

ghorrocks, can you help me in find an appropriate tutorial for this problem,
and what does isolated mesh regions mean? can you explain the problem which causes this error?
thanks so much

ghorrocks August 5, 2010 19:12

It means you have several meshed regions which do not connect. It is a meshing error usually. Need to remesh and connect the mesh up properly.


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