CFD mesh with BL for external flow with symmetry plane

mvass
mvass Altair Community Member
edited October 2020 in Community Q&A

Dear CFD users,

 

I am desperately trying to create a 3d cfd mesh with BL using Hypermesh. My geometry is perfectly connected with the control volume faces and the surface mesh created on the geometry (defined as 'wall') and the control volume faces has passed all sanity checks (connected elements, no duplicates, no free edges) resulting to a 'watertight' 2d mesh ready for 3d meshing. With these conditions a 3d mesh from the 2d boundaries is created without any problems. My problem is to create a 3d CFD mesh with a given boundary layer on the component named as 'wall' (which is the body that I wish to investigate).

 

Although the mesh is created (with the boundary layer specified), it is not connected to the symmetry plane as I want: I was expecting to see only the elements of of the symmetry plane to change their topology ('shape') in order to connect with the boundary layer created on the wall and the rest elements remaining as they were (or close). Not only this does not happen, but a BL is created both on the wall elements and  all elements of the surface plane.

 

The attached images show the control volume and describe the problem I am facing. Could you please let me know if what I want can be done in Hypermesh? How do I define my 3d meshing strategy in the CFD option?

 

Thank you in advance for your kind assistance.    

<?xml version="1.0" encoding="UTF-8"?>control_volume.jpg

<?xml version="1.0" encoding="UTF-8"?>wall_symmetry_connection.jpg

<?xml version="1.0" encoding="UTF-8"?>BL_created.jpg

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Answers

  • QuyNguyenDai
    QuyNguyenDai Altair Community Member
    edited April 2020

    With only some pictures, I don't think somebody can help.

  • mvass
    mvass Altair Community Member
    edited April 2020

    What was exactly the part of my question that you didn't understand and therefore need additional info?

     

    Can you provide any meaningful assistance? If not, please let someone else try.

     

    Thank you.

     

    PS: To anyone with a sincere will for support: I'll be happy to send a simple example of a similar closed mesh (body, symmetry zone, faces) for trying to create a BL on the body as per request. 

  • mvass
    mvass Altair Community Member
    edited April 2020

    I managed to do it (without any assistance, thanks).

     

    In the picture attached, a correctly BL is created on the wall component surface mesh and the attached symmetry plane mesh changed to connect with the BL created. The example (which I can share with anyone interested) consists of a brick object ('wall') inside a control volume with the following faces: inlet, outlet, symmetry and farfield. In order to create the volume CFD mesh from the existing 2d surface mesh I went to CFD tetramesh-->setup BL parameters-->setup tetramesh parameters-->Boundary selection: select 'wall' in with BL (fixed) menu and the rest of the surface mesh (inlet, outlet, symmetry, farfield) in the w/o BL mesh (float). Leave all other options as seen in the image attached.

     

     

    <?xml version="1.0" encoding="UTF-8"?>CFD_tetramenu.jpg

    <?xml version="1.0" encoding="UTF-8"?>correct_BL_mesh.jpg