I'm designing a rocket nozzle, so I know that there's going to be high mach number, and when I use the solver WITHOUT high mach number option selected, it completes fine but gives me a bunch of warnings about supersonic flow. When I select the High Mach Number option, it just fails right at the beginning of the calculation.

Warnings:
* The flow has high Mach number, the "High Mach number flow" option is recommended.
* A vortex crosses the pressure opening
* Supersonic flow is detected within a considerable number of cells

Any ideas?

UPDATE: I found out where the log is for the solver (window 2. Derp.)

I got the following:

• Mesh generation started
  
• Mesh generation normally finished
  
• Preparing data for calculation
  
• Calculation started - Iteration 0
  

Then in the main window it says "Solver abnormally terminated" :/

UPDATE 2: I changed from 2.75 MPa environmental pressure (400 psi) (laminar) to .339kg/s mass flow rate based on the propellant masses and the burn time of the motor. Solver had no problem after that. Something I don't know about the various opening types, I guess?