Hi. Trying to learn to use CFX i found a huge lack in the tutorial material gathered into CFX and around the web. I have a whole fluid domain, and i need to split it into two different parts, in order to obtain two different assemblies so that i can set the rotating impeller domain and the statoric one. The problem is that i don't know how to operate the split. Does it need to be operated in CFX-Mesh? Or in DM? If so, does exist a proper feature to do so? Otherwise i guess i have to "manually" cut the whole fluid volume and save the result as statoric_fluid_volume.agdb, operate the complementary cut and save as impeller_fluid_volume.agdb. Then import both files into cfx-mesh. Is this the right way? It seems quite coarse to me.

Futhermore, I'd like to have any suggestions in order to place correctly the interface in order to set up a good simulation (for example, tutorials suggests not to place the interface too near to the impeller, since it would create matching/convergence problems).

Thank you very much.

Hi. Yes you are right. You need to split the geometry in a CAD software, i.e. Catia or DM. Then mesh them respectively. After that they should be imported into CFX pre and use the domain interface function to connect the two domains.

I never seen a article discuss the proper interface position. Based on my experience, place the interface at the middle between blade outlet and pump housing is a good choice.

Read the Best Practices Guide for Turbomachinery in the on-line help. There is a section on domain interface setup. In DM, draw a line to cut your part and revolve it using the Cut Material operation, setting the thin surface option on and specifying 0 inward and 0 outward thickness. This will slice your model and keep the parts separate. You can then mesh them in one go in CFX-Mesh, or independantly.