Supersonic Flow in UG/NX

[scottneh]

Hello, has anyone simulated supersonic flow in UG/NX? I have a fairly simple flat plate with a small protrusion. The simulation runs well up to mach 1 or so. when I try to run it at mach 1.08 it crashes. I talked with Maya tech support (they make the CFD package for UG) and they told me that the software isn't tailored for flows with "external shocks". The problem is that I am simulating flow through an arbitrary fluid volume which could be from the inside of a duct or inlet so from that perspective what's an "external shock"?

If anyone has done any simulation of supersonic flow in UG I would really appreciate any help you can offer. The up loaded picture is a close up of my model at Mach 1.

Thanks
Scott

 

[btrueblood]

The solver equations and methodology for CFD change across Mach 1, sounds like their embedded solver is an elliptical solver (subsonic) only, and can't handle the hyperbolic (supersonic) flow field.

 

[scottneh]

Thanks for your response. They advertise being able to run supersonic flow simulations and they have an inlet condition for supersonic flow. So I'm thinking that there must be some sort of condition under which their solver will work.