This question is more about the abilities of Flow Simulation, and not about a specific setup. I have a compressed air supply (60 psig) and I'm curious if Flow Sim could help me design a de Laval nozzle to increase the mass flow rate. Just dumping out 60 psig to ambient through a tube would choke the flow, and I want to maximize my mass flow rate. I know it's possible to simulate low Mach numbers (<.3) and supersonic flow separately, but how does the software do with compressible flow right at the sonic regime? Would I get reliable numbers for the expansion through the nozzle?