CFD on a Hyperloop Pod

I’m conducting a CFD simulation for a pod traveling through a tube at different velocities. The simulations were conducted at an air pressure of 860Pa. The results were generated at lower velocities without any issue but at higher velocities (500kmph and above) kept showing errors. I tried to make the mesh finer as suggested by Simscale but the error didn’t resolve.
Can you please have a look at the simulation settings and suggest any changes to improve the simulation results.

https://www.simscale.com/workbench/?pid=270076544448475248&mi=run%3A12%2Csimulation%3A2&mt=SIMULATION_RUN

Hi!

This air pressure is definitely low - are you simulating a very high altitude?

On a side note, it may be a good idea to try and ramp the velocity at the inlet, as seen in our Compressible flow tutorial for external aerodynamics (Section 2.2.D). If the velocity initialization/ramping is done slowly, the simulation gets more stable in the first iterations.

Cheers