[ugurtan666]

Hello SU2 users,

I am interested with the approximate Riemann solvers for a period of time. I am reading book of Toro, Riemann Solvers and Numerical Methods for Fluid Dynamics.

It is easy to imagine the Riemann problem for first order spatial accuracy in which the values in cells are piecewise constant. However, this becomes piecewise linear for second order spatial accuracy by MUSCL approach. If I am not wrong, a slope limiter is also applied for the case to obey TVD condition.

Finally, there is a slope in each cell and the cell face values can be calculated by that slope. Here is my question.

What is the method of calculating flux in the cell faces' right and left sides as input to Riemann problem?

Because Toro says that the topology of the Riemann solution is parabolic for piecewise linear initial conditions. MUSCL-Hancock method is proposed for make the Riemann problem piecewise constant but I could not understand from source code what is done in SU2 for Euler-implicit temporal discretization.

The inputs of Riemann problem are obtained directly from the limited slopes or from making the scheme piecewise constant as proposed by MUSCL-Hancock method?

Thank you very much for your patience