Dear who can answer the phenomena formation?

Now, I am simulating the virtual impactor that ist the equipment for separate the small particle (about 0.03-0.3 microns) from the air stream.

First I simulate only one phase of air to see the profile of air velocity and the motion of it but I still cannot get the good profile. The good profile of air that will make the good separation of small particle will come from the shock wave phenomena that occur inside the impactor. The velocity should be change very very rapidly in front of the probe (shock wave). But in my work, it still not the shock wave because the velocity doesn't change rapidly. It still change step by step from 620 m/s to 500 m/s and then 400 and so on until 50 m/s.

Therefore, I would like to ask you about: The equation in CFD especially in CFX5.7 program can describe the shock wave phenomena or not? Or I have to program the Fortran code into the program?? Or I have to choose any features in the CFX program to make it can describe the shock wave phenomena

Thank you very much for your helping

Regard, Nucharin

Yes it can model shock waves, but you will need a lot of mesh to capture the phenomenon. Try a simple problem frist, say 2D and then build up to your problem. Try using the mesh adaption that should help.

Thank you very much for your suggestion "Khun Funster". I will try to model again. When I get the result, I will tell you later.