Hi, this is Fillia 
I have a few comments:
-
For simulations that reach Mach numbers > 0.3, the compressible analysis type is suitable.
-
Make sure to include the viscous forces too.
-
What about simulating half the model to save resources? It seems symmetric to the plane normal to the x-axis. Then you could refine your mesh even more. (For example, this project uses Symmetry combined with the Hex-dominant parametric algorithm: Hex-Dominant Parametric Meshing of Front Wing | SimScale)
-
With your current Simulation Control settings, the run is set to perform 15000 loops. What about trying 1500 instead? If this doesn’t converge by then, you can increase this end time and continue the run afterwards (have a look here: Can I Continue an Existing Simulation Run in SimScale?)
-
I went through the mesh refinements and didn’t find an Inflate boundary layer for the body (correct me if I am wrong). This is important for the simulation, so maybe you should considering adding this. (What is y+ (yplus)?)
Let me know what you think!
Best regards,
Fillia