Change parameters for Hybrid mesh

karananand · July 16, 2010, 02:09

I have a hybrid mesh (Tetra with hex core). I can adjust the max element size for tetra and hex. however, is there a way that I can define the number of layers or max height (thickness) of the tetra elements with the hexcore option enabled?

What I have seen is that the hex-core automatically determines the height of the tetra and hex layers. I tried changing the tetra ratio, height etc from the surface mesh, but nothing seems to work!

Also another question. Is there a way that I can increase the mesh density of the tet in one area (closer to one wall and reducing outwards until it hits the other wall) without the mesh density option in ICEM. I want a gradual decrement in mesh density for the unstruct tet mesh. (again using the height ratio didnt help!!

-mAx- · July 16, 2010, 02:15

which software?

karananand · July 16, 2010, 13:12

Sorry: ICEM
I have added couple of pics to show the coarse mesh:

http://img689.imageshack.us/gal.php?...ucthexwith.jpg

PSYMN · July 18, 2010, 17:37

Nope, sorry, the Hex Core doesn't provide that option to set the offset to the user...

Instead of Hex Core, I usually use the 12 tet to 1 hex conversion. This basically turns the octree tetras back into the original hexas...

As for wanting a smoother transition in tetra mesh size from one wall to the other, your best bet is to use the Delaunay method (perhaps with TGlib AF). The size transitions are built into OCTREE's algorithm, but you could start with Octree, then delete the volume mesh and smooth the surface mesh with laplace, then generate the delaunay fill and you will get your nice smooth transition.

July 16, 2010, 02:09	Change parameters for Hybrid mesh	#1
karananand New Member Karan Anand Join Date: Feb 2010 Posts: 23 Rep Power: 16	I have a hybrid mesh (Tetra with hex core). I can adjust the max element size for tetra and hex. however, is there a way that I can define the number of layers or max height (thickness) of the tetra elements with the hexcore option enabled? What I have seen is that the hex-core automatically determines the height of the tetra and hex layers. I tried changing the tetra ratio, height etc from the surface mesh, but nothing seems to work! Also another question. Is there a way that I can increase the mesh density of the tet in one area (closer to one wall and reducing outwards until it hits the other wall) without the mesh density option in ICEM. I want a gradual decrement in mesh density for the unstruct tet mesh. (again using the height ratio didnt help!!

July 16, 2010, 02:15		#2
-mAx- Super Moderator Maxime Perelli Join Date: Mar 2009 Location: Switzerland Posts: 3,297 Rep Power: 41	which software? __________________ In memory of my friend Hervé: CFD engineer & freerider

July 16, 2010, 13:12		#3
karananand New Member Karan Anand Join Date: Feb 2010 Posts: 23 Rep Power: 16	Sorry: ICEM I have added couple of pics to show the coarse mesh: http://img689.imageshack.us/gal.php?...ucthexwith.jpg Last edited by karananand; July 16, 2010 at 13:53.

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July 18, 2010, 17:37		#4
PSYMN Senior Member Simon Pereira Join Date: Mar 2009 Location: Ann Arbor, MI Posts: 2,663 Blog Entries: 1 Rep Power: 47	Nope, sorry, the Hex Core doesn't provide that option to set the offset to the user... Instead of Hex Core, I usually use the 12 tet to 1 hex conversion. This basically turns the octree tetras back into the original hexas... As for wanting a smoother transition in tetra mesh size from one wall to the other, your best bet is to use the Delaunay method (perhaps with TGlib AF). The size transitions are built into OCTREE's algorithm, but you could start with Octree, then delete the volume mesh and smooth the surface mesh with laplace, then generate the delaunay fill and you will get your nice smooth transition.