Rusanov flux computation
 

Hi All,

I have a basic doubt in Flux computation in unstructured grids (DG scheme). The Rusanov fluxes are given by

F = 0.5*(FL+FR - Smax * ( QR - QL ) )

Can anyone please explain the transformation of the fluxes and solution vectors from the cartesian to local face coordinates in the process of solution evolution?

Is the following procedure correct?

1) Transform Q to face local coordinate QT
2) Compute Flux FT(QT)
3) Transform the flux vector back to cartesian coordinate

or, is the following one prefferable?

1) Compute 3D cartesian fluxes
2) Estimate wave speed (Smax) along normal direction
3) Compute normal flux (F .dot. n)

Not sure what they use in common...

Your help is much appreciated. Thanks.

See

http://www.cfd-online.com/Forums/blo...red-grids.html

Hi Praveen,

Thank you for the link. This is exactly what I was searching.