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-   -   Troubles importing geometry (https://www.cfd-online.com/Forums/star-ccm/84021-troubles-importing-geometry.html)

Txa January 18, 2011 10:39

Troubles importing geometry
 
Hi.

I've got problems importing suface mesh. I can't do it with .stp, .igs or catia files ("sever error: error during CAD import" error appears).

I can import it from a .stl file, but after apling all the options and trying to "generate surface mesh" it takes a lot of time and finally stops when "current number of faces: 12000000" and "Exception (bad_alloc):
A request for memory failed. This is typically due to insufficient virtual memory" error appears.

Why is this happening? Can anyone help me?

I'm using star ccm+ 4.04

Thanks

RobertB January 18, 2011 12:48

Had you considered using one of the current versions? I believe they are up to 5.06. There is a good chance any error will have been fixed, assuming it is with the code rather than the CAD.

I doubt very much support will give you any real help on a version that old.

rwryne January 18, 2011 13:05

How much memory does your computer have? It seems like you are opening a model with a lot of complexity to it and you are exceeding your available memory (both RAM + virtual memory)

Maybe try importing the model and turning down the tessellation density?

Txa January 18, 2011 13:46

Quote:

Originally Posted by RobertB (Post 290973)
Had you considered using one of the current versions? I believe they are up to 5.06. There is a good chance any error will have been fixed, assuming it is with the code rather than the CAD.

I doubt very much support will give you any real help on a version that old.

thank you for your replay

Maybe you are right and with a newer version the trouble fixes. I'm just starting and learning with the program and the v4.04 is the only one I was able to obtain.

Do you know where I can get a newer version?

RobertB January 18, 2011 14:02

Download it off the cd-adapco site.

abdul099 January 18, 2011 15:31

Of course, the newer versions offer a lot of nice features. But even an old version like 4.04 (which in theory should have been released in May 2009) should be able to handle a big mesh. When this is not possible, it's likley that your machine doesn't have enough memory. Just think about the "bad alloc"-message. It even points you to a memory issue, one can read "This is usually due to insufficient virtual memory".

Maybe you can give some details about your machine you are using and we can tell you whether it's worth to keep on going on a model with the same complexity.

RobertB January 18, 2011 16:15

I'm sorry I misread the initial comment. My experience is that when CCM+ has severe problems generating a new surface mesh that there is an error in the CAD model that is causing it problems. Finding that error is typically not trivial. Try a much coarser mesh and see what happens.

Either that or you are making much too fine a surface mesh. 12,000,000 cells on the surface would result in a pretty large grid unless the mesh is 'surface dominated' such as a narrow channel heat exchanger.

Does the absolute base size make sense for your model?


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