[jbritton]

Hi All,

I was just wondering what are the primary differrences between the two meshing methods, and does it lead to one being more accurate than another?

My issue being, as far as I know the hex has an advantage in the fact that each element has more boundaries and more communication with bordering elements. But at the same time a hexagon is jus a collection of tetrahedrals and obviously these are all communicating with each other.

But if some one could explain the differences in detail, or provide some links to papers that look at this that would be great.

Thanks in advance.

Edit: Sorry I dont really mean Hex mesh in the title I was more refering to the polyhedral mesh used in CCM, and a compare and contrast between this and the normal tetrahedral meshing used in CFX

[jbritton]

anyone have any ideas?

[Hamidzoka]

Dear James;
Tet meshes are more flexible with geometries than Hex meshes.
so, Tet meshes are usually applied to complicated geometries. using Hex meshes for complicated geometries needs the mesh size to be so small to attach the boundaries properly. so it may cause the number of meshes considerably increases.
the main benefit of Hex meshes is that they converge to the solution with meshes less than Tet ones. in fact if you are allowed to use Hex meshes in your geometry, you will solve it with less meshes and therefore less numerical efforts.

regards

[Jade M]

In my experience with CFX,

• Hex meshes both mesh and solve faster than tet meshes. However, not all domains can be hex meshed so tet meshing is required. Also, hex meshing with inflation may be limited. Hex mesh wherever possible.
• Increase the volume of the mesh that is hexahedral by slicing the domain into simpler sweepable volumes. Then some volumes can be sweeped (and thus hex meshed) and the remaining volumes can be tet meshed. Be sure to form new part with the multiple domains for conformal meshing.
• The hex-dominant meshing method should only be used for structural simulations as it does not allow for inflation.