Projection code: lid driven validation
 

Hi all,
I have written a C++ code for simulating flow using projection method. and i have set up the domain to simulate lid-driven cavity flow for validation. But i am unaware of the pressure boundary conditions that need to be implemented at the boundaries. I am using a fully staggered grid and presently using a boundary condition of dp/dn = 0 on all boundaries including the boundary in which shearing is done. I find that the poisson equation is giving a peak at the corners and diverging (i am using gauss-seidel method to solve the poisson equation). Can someone tell what the reason could be?

Regards,
sgp.