Outlet

At an outlet the velocity is assumed not to change in flow direction. Furthermore, the mesh is assumed such that $ \boldsymbol{ j}$ corresponds with the flow direction. From this we have

$\displaystyle (v_i)_e^{(m)} = (v_i)_P^{(m)}$ (555)

(assuming that e is the face at the outlet) and the first term in Equation (551), which takes now a similar form as in Equation (554) drops out.