boundary conditions on MAC grid
 

Hi, I want to know how to descritize some boundary conditions on Mac grid with finit difference scheme. My domain is: i=1, X

j=1, Y for exemple at the entrance: gradu=gradv=0 (no axial variations), is this correct? u(i,1)=u(i,2)

v(i,1)=v(i,2) A second question: the boundary conditions on fluxes and residuals ( for interface capturing methods) are they the same as boundary conditions on velocities in each direction of the domain? Can any body help me and if there is a good book that treat this problem in details.