Anisotropic mesh gradation

[OmkarJ]

I thought I read somwhere that SimCFD 2014 supports anisotropic transition from wall to internal elements for prism elements. I couldnt find much the reference of it in the doco. Is it there, and if yes, what is it?

Thanks

Omkar

[Royce_adsk]

Hi OJ,

Do you mean the mesh enhancement gradation setting?

http://wikihelp.autodesk.com/Simulation_CFD/enu/2014/Help/0532-User_s_G532/0698-Process698/0719-Setu...

-Royce

[OmkarJ]

Royce,

I do know about the gradation, and btw, this is a really good addition. What I was curious about is term "anisotropic gradation" and I think I saw its mention in one of your comments in the case I generated (08379075). For the sake of this conversation, let me put the excerpts of the comment here:

+------------------------------------------

The future Y+ adaptation is through the general mesh adaptation option.  This does a much better job to generate a good mesh transition and couple that with SST and 10+ layers of wall elements with anisotrophic mesh transition from the wall and you can really start to get an excellent mesh.  When I am using Ke in 2014 I typically set a value of 100 or 150.  When using SST I will shoot for 100 or less depending on the number of layers that I have used and the amount of layer gradation.

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Can you explain what exactly that is? Is it equivalent to "Edge growth rate" in the lateral directions? Or is it about the localised mesh adaptation for Y+?

Thanks

Omkar

[Royce_adsk · Accepted solution]

Ahh.. I remember that post.

You can use this flag (mesh_anisotropic_blend) to turn on anisotrophic blending. There are no real controls for the flag, but does allow anisotrophic elements away from the mesh enhancement layers to be generated. 

Give it a shot with a simple model!  It can add a lot more mesh and take longer to mesh, but can be useful for some geometries.

-Royce