I am currently simulating gas flows through a pressure relief valve, due to the compressible nature of the flows there are significant pressure and velocity gradients in the flows. There are also shock waves within the valve that have to be captured in the simulation.

My question is regarding mesh refinement, so far using the controls I can refine the mesh next to a surface or wall, this help my simulation but I also need to have refinement control away from the wall well into the fluid flow to capture the shocks.

Anyone any ideas on how to refine the mesh in this manner?

Thanks in advance