Boundary layer generation on baffles and T-junctions.

Jo th,

Boundary layer elements are required for CFD analyses and these are created in the CFD tetramesh panel and other options in HyperMesh like 2d bl mesh in the utility tab when in the engineering solutions > cfd user profile.

The CFD Tetramesh panel can be used to generate hybrid grids, containing hexa/penta/tetra elements in the boundary layer and tetra elements in the core or fare field.

Use the boundary selection sub panel within the cfd tetramesh panel to select the elements/components that define the surface area on which you need to generate boundary layers. (The panel layout changes depending on your choice of boundary layer options, which are determined by a toggle in the bottom-left corner of the panel labeled Smooth BL or Native BL.)

It is recommended to use the Smooth BL method, which produces a smooth orthogonal boundary layer and better element quality.

See HyperMesh > HyperMesh Panels > HyperMesh Panels Listed Alphabetically > cfd tetramesh panel:
Boundary selection subpanel in the help, (accessed by simply pressing h on the keyboard)

See Engineering Solutions > CFD Tutorials

Hey,

I do it in the way you described. But I receive a error message, that the mesh is not enclosed.

And HM shows me the edges, which have no connection, because they are from Buffles and T-Junctions.

What do I wrong?

best regards
jo th

Update:

Problem solved. I have had some bad elements on my geometry.
Thank you

now I have an other problem.

Hypermesh shows me an error, that 'Volume failed tetra meshing'.

Can someone explain that error?

Check if your volume is enclosed (water tight) using tool edges and make sure your surface mesh is of good quality.

you may need to use float instead of fixed if you are using a quad surface mesh. Exactly what options are you using currently and when do you get this error?

You may need to start with a tria mesh, as quads are anyway split to trias before meshing, follow the checklist below