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[benjaminwalz]

Hello everyone,

i am trying to set up a CFD simulation of a gyroid geometry. The gyroid divides space into two volume sections. On the one side the will be vapor and on the other side liquid. The application of this geometry is a counter flow heat exchanger.

I have problems with generating a mesh with acceptable quality due to the complexity of the gyroid surface. I have tryed various methods like implementing facemeshing and/or facesizing of the edges, but the results were not satisfying.

Can anyone offer help how to mesh this geometry for modeling heat transfer?

mesh file

Thanks and best regards

[Keyur Kanade]

please use tet mesh with prism layers. please go through some videos on tet mesh and inflation. 

https://www.youtube.com/watch?v=RELLrEJ9chg

https://www.youtube.com/watch?v=lrEHXizrhC0

Regards,

Keyur

 

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[Aniket Chavan]

Ansys staff are not allowed to download anything on the student community, which quality criteria are you checking? (sorry you have included the snap, but language barriers!)

Have you tried the following options in the mesh details:

 

-Aniket

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[benjaminwalz]

Thanks for your answer.

I did tried tet mesh at first, but the quality of the mesh was not good enough. The simulation did not converge.

Also i tryed to inflate the contact region between the two fluids, but with no sucess. The mesh generation aborted with error.

[benjaminwalz]

Thanks for your answer. The quality criteria is orthogonal quality. The cell with worst quality is below 5e-3. I tryed to fix this with the reapir mesh tool and improve mesh quality tool within fluent, with no success.

I will try the options you have suggested.

[benjaminwalz]

One problem of the geometry is that the contact region consists out of many faces (<8000 small surfaces).

Here a picture of the geometry for better understanding.

[Rob]

My guess is that you have lots of sharp angles on the matrix surface. When you mesh this is creating very poor cells in the system. If you look at the quality graph and adjust the scale you'll be able to pick the columns of rubbish cells which will show you where they are. 

 

[benjaminwalz]

Yes the surfaces are creating angles, but the angles are not sharp. The bad cells are located in the free space of the volumes too, which i dont understand.

Here i used element quality criteria.

i will try this mesh and see if the solution will converge.

[Keyur Kanade]

in spaceclaim, please use pull command and create fillet or chamfer at those sharp angles. this will help you to avoid these bad elements. 

Regards,

Keyur

 

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