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-   -   Mesh Problem (http://www.cfd-online.com/Forums/star-ccm/106104-mesh-problem.html)

Giannis August 18, 2012 15:03

Mesh Problem
 
Hello Everyone!

I have a very crucial question, concerning the mesh development of my model. I am working on STAR CCM+, and I would like to ask whether it is possible to have good results in case i study a heat transfer problem, and the base size between the two regions is significantly different.
For instance, if I have a pipe (base size=0.04m), and this create an interface with a wall, whose base size is 0.5m, is it possible to provide me credible results?

I have noticed that mesh quality is poor between two region, but it is difficult to reduce significantly the base size of wall, since my geometry is huge, and then the computational power is proved to be limited in that case.

Do you know any mesh factor that could give me a good mesh between a small and a high base size regions?

I have tried almost everything but with no luck so far:(

Thank you a lot in advance for your help!

rwryne August 19, 2012 10:37

Quote:

Originally Posted by Giannis (Post 377647)
Hello Everyone!

I have a very crucial question, concerning the mesh development of my model. I am working on STAR CCM+, and I would like to ask whether it is possible to have good results in case i study a heat transfer problem, and the base size between the two regions is significantly different.
For instance, if I have a pipe (base size=0.04m), and this create an interface with a wall, whose base size is 0.5m, is it possible to provide me credible results?

I have noticed that mesh quality is poor between two region, but it is difficult to reduce significantly the base size of wall, since my geometry is huge, and then the computational power is proved to be limited in that case.

Do you know any mesh factor that could give me a good mesh between a small and a high base size regions?

I have tried almost everything but with no luck so far:(

Thank you a lot in advance for your help!


Assuming you mean you want to have an interface where the fluid region has a smaller base size than the solid region, yes you can do this with an indirect interface. This means they wont be conformal (obviously, with different mesh sizes...)

Giannis August 21, 2012 10:31

Hello rwryne and thank you for your reply!

I tried what you had mentioned to me, but now I have the following:
Type ''star.common.MixingPlane inflowBoundary'' of boundary ''(the name name of the Indirect boundary)'' is incompatible with available mo[/U]dels.

Concerning the models, I tested both options:
1)Prism Layer mesher, Surface remesher, Trimmer
and 2)Prism layer Mesher, Poluhedral, surface Remesher

None of those work.

Do you have any suggestion?

Thanks anyone for your help!

Giannis

rwryne August 21, 2012 12:58

Oh, you are using a mixing plane interface. Try using the Mapped Contact interface instead.

Mixing plane interfaces are fairly specific to turbo machinery problems.

abdul099 August 28, 2012 19:52

Complaints about interfaces being incompatible with some models usually mean incompatible with some physics models, not meshing models.


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