The relationship between the explicitly advanced velocity component and velocity at the previous time step may be written as

(33.3)

where is only the contribution from convection and diffusion terms. On the other hand, the corrected velocity component (unknown) will be related to the corrected pressure (also unknown) in the following way:

(33.4)

Form Equations (33.3) and (33.4)

Where the pressure correction may be defined as

Neither the pressure correction nor is the quantity is explicitly know at this stage. Hence, one cannot be calculated without the help of the other.

Calculations are done in an iterative cycle and we write