The project concentrates on how the actual inflow to the rudder is in behind hull and propeller conditions, provided the additional difficulty that in harbour manoeuvring conditions the ship can be sailing at slow speeds ahead or astern, while the propeller can be providing a forward or a backward thrust. The combination of the two signs of the ship’s speed and the propeller rate are commonly defined into 4 quadrants. With the use of CFD more insight should be obtained for the inflow prediction in these four quadrants as to enhance the prediction of the forces and moments delivered by the rudder in harbour manoeuvring mode.