Exact Riemann Solver in SU2
 

Hello SU2 users,

I have added an iterative exact Riemann Solver in SU2 for ideal gases taking Toro's Riemann solvers book as guide. It generates realistic results for subsonic flows for both first and second order.

However, I got unrealistic results for supersonic flows. I closed the second order option and I got realistic results again. I tried to restart the run from converged first order solution but it produces unrealistic results (I have 5-6 Mach number in the domain in spite of 0.7 free stream Mach number for a 2D airfoil case) again.

I am suspicious about the validity of Riemann problem by assuming piecewise constant function.

Should I solve the Riemann problem for piecewise linear assumption?

As far as I understood from the code, HLLC scheme solves the problem as piecewise constant by Q_i and Q_j conserved quantities. If it is so, Can it be a problem for high CFL cases?