Radiative boundary Condition
 

Hi everyone,

I am attempting to incorporate a radiative boundary condition into an LES code. The condition I'm using comes from the Gresho and Sani paper (Int. Journ. Num. Methods Fluids, 1987), and I'm trying to incorporate it onto a MAC style grid. My requirement is that dP/dx =0 along one of my lateral boundaries.

Can anyone give me any pointers as to how to do this? Clearly, I need to set (Po - Pw)/l = 0, but I am unsure as to how to solve for the required v-velocity node (in this case, Vnn)

Thanks,

Andrew