Creating 3D mesh in ICEM with defined boundaries
 

Hi everyone,

I am having trouble creating a 3d mesh for a LES simulation I am doing for a supersonic free jet. I have created a 2D geometry and structured mesh in ansys (find attached) and am quite happy with it. Being LES, I need a 3d mesh, so I now need to revolve it 45 degrees to make a 1/8th section. I am running the simulation using OpenFOAM but doing the meshing and geometry in ansys. However I need to define the boundaries in ansys so that when I export it to OpenFOAM it recognises them and BC's can be applied.

I need to define an inlet surface, the nozzle wall surface, and the freestream surface. Also I need to set up a cyclic pair on each side surface (periodic in the circumferential direction).

I exported the 2d mesh from ansys in .msh format then imported it to ICEM and extruded it to 3D (also attached) and it looks great, however I need to redefine the boundaries. Is there any way of defining boundaries at this stage? Or do I have to define them on the geometry?

I'm super confused, what is the best way to do this!!!!!!

Attachment 15421

Attachment 15422

Attachment 15423

If i'am not wrong, Boundaries has to be defined in geometry, then associated to the edge in a structured mesh. once the .msh is created, it's too late.

It would have been easier to name the edges before you generated the initial mesh, but it is not too late. It is just a little more effort. ;)

In the display tree, right click on parts to create a new part. Lets call the first one "INLET".

Then with only shell elements displayed, go over to that are of the model and select the shells you want to put into that part.

There are lots of selection tools to help you get just the ones you want. For instance, you could use a polygon (p) or a box, or your could select a single element on a face and floodfill to angle. You can even set the angle, but I think the default of 30 degrees should work fine in your case.

Thanks for the help guys, I ended up using ansys mesher and defined the cyclic boundaries using fluent.

Cheers

( i make the 2d model of shell and tube heat exchanger and mesh it but when select heat exchanger model in fluent it give error that primary and auxiliary regions are not overlapping ..... so plz help me what i do .... i'm new to use ansys