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-   -   Limiters for 2nd order solvers (https://www.cfd-online.com/Forums/main/152-limiters-2nd-order-solvers.html)

 Heinz Wilkening September 2, 1998 06:31

Limiters for 2nd order solvers

Ciao everybody,

I already posted this massage, but the last time there was a typo in the subject, so I am not sure if this has confused some readers. To be sure I rersend the massage.

We have developed our own NS-solver for explosion modeling. The grid is based on triangles (2D) or tetraherons (3D). Control Volumes (CV) are constructed around each vertex of the tri/tet by the medians of the faces of the tri/tet. Between neighbour CV a 1-D Rieman Problem is solved (Gudonov's method), using e.g. Roe's app. Riemansolver. For the 2nd order solver we calculate a gradient inside each CV and use this to extrapolate to the neigbours (van Leer's method for 2nd order solvers). To prevent instabilities the gradient has to be limited. We tried different limiters, all of then limited to much in the 3-D case, so our solution was only 1st order in 3-D. We think the reason might be, that we have much more neighbours in the 3-D case than in the 2-D case. Most limiters work fine in 2-D.

Does someone have similar experience? What limiter would you recommend?

Thank you.

Heinz

 k_tafazoli March 14, 2013 04:40

Van leer second order and AUSM+

Hi, I've got a fortran code for solving 2D compressible flow over an airfoil with the method of first order van leer flux vector splitting . I have to change it to second order van leer flux vector splitting method . Can you please help me on how to do it? It's also possible for me to solve this project with the method of AUSM+ . Are you familiar with this method? can you help me with it please?