ICEM Boundary Conditions Problem
 

Hello everyone, I'm trying to create a mesh in ICEM for an outlet duct using the blocking method, but when I import the mesh in CFX-pre the named selections have different associated surfaces than before and as a result I can't specify the correct boundary conditions. The geometry starts from a cylinder with a cone inside, and slowly transforms into a rectangular duct, with the use of 4 beaks (image 1). Despite associating each edge of the block to a beak surface (image 2), in CFX-pre half of each beak surface is merged with the nearest tangential wall surface and appears as one surface (image 3). Any ideas to overcome this problem would be appreciated.

Hello Petros,

Have you done the add to part correctly in ICEM? i.e. make sure that each part is added only to the correct section.

Hello Kira and thanks for your reply. It's been a while since i posted this and since then I've chosen to make a hybrid mesh, because I couldn't find a way to make a good quality hexa mesh in a geometry with so many closely linked curves.


All of the "add to part" commands where correct, the problem is that in CFX Pre some parts (surfaces) wouldn't show up in the boundary condition setup, or they would show up as merged with the neighboring surface.


Looks like it had to do with the block split and edge association process, even though I had as many faces as I had surfaces. Don't know what could be the problem.



Anyway, even if I found a way to do it, the quality metrics are very bad in general, because many elements close to walls were highly skewed. Hybrid mesh works better in my opinion, because I create prism layers close to the walls, and the rest of the volume is tetra.

Hello Petros,

I am glad you discovered and decided to use they hybrid mesh and it was able to solve your problem. I was going to suggest this next because of your slightly complex (i.e. with those curved surfaces) geometry.

That is strange about the surfaces. Those issues could have been a bug/glitch with ICEM.

Glad you found a solution in the end!