SIMPLE Scheme for open channel flow
 

Could anybody help me with applying the SIMPLE scheme to shallow water eqs in which the pressure and depth is implicit coupled? Do I have to transfer the depth to pressure before every iteration and after solving pressure-correction eqs, tranfer it back to depth? Then how to deal with the boundary conditions? When I give known depth at inlet, how about pressure and pressure correction in the interation computation? thanks a lot for any advice!