Unusual Results Using MUSCL with SST-V2003m
j-signorelli opened this issue · 2 comments
Describe the bug
I noticed I was converging to quite different solutions when MUSCL is on v. off for a much larger case I am doing using SU2 with SST-2003m, so I created a smaller 2D case to test out why this may be occurring. Below is a screenshot of one of the meshes, where the pinkish line indicates a value for an interface that I plot heat fluxes from. I have generated several meshes with increasing level of refinement from A to D.
It appears that there may be either a misunderstanding on my part with the implementation of SST-V2003m w/ MUSCL, or that a bug exists in SU2 for it. I got very unusual and different results when using MUSCL vs. not. To further look into this, I also completed additional simulations using KIND_TURB_MODEL=SA, which got me much more reasonable-looking results. Please see the plots below:
Lastly, here is the config file:
config.txt
Note that the "MUSCL=ON" in the plots indicate the solution for both MUSCL_FLOW=YES and MUSCL_TURB=YES. That is the only difference between config files. Also, I tried using MARKER_RIEMANN, MARKER_OUTLET, and MARKER_SUPERSONIC_OUTLET on the outlets with no success on fixing this discrepancy, so I believe it is not related to the boundary conditions.
Bug report checklist
Please make sure that you have followed the checklist below, many common problems can be solved by:
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And when you say MUSCL=OFF is it also for the flow? If so I would not be surprised that a first-order simulation gives different results.
Hi @pcarruscag , that is correct. If this is no surprise, then this is no bug. But it seems unusual to me to have this stark of a difference. I rapidly got mesh convergence for SA using MUSCL as shown, but not even close for SST even on additional finer meshes I generated. I also noticed this occurring with pressure, which truly makes no sense to me from a flow physics standpoint:
