Numerical study of the flow field around a ship hull including propeller effects

Although extensive research concerning the flow around ship hull has been carried out in the past decades it is still difficult to calculate the flow around the hull including the propeller. It is well known that the flow behind the ship is affected by the propeller, and the hydrodynamic performances of the propeller are dependent on the incoming flow velocity. In the present paper the viscous flow around an existing vessel is computed including the propeller action. This analysis combines the numerical investigation of flow around the ship with propeller theory to simulate the hull-propeller interaction. The computations are performed using Shipflow code and in-house codes for propeller design. The designed propeller geometry is specified in the flow module in order to obtain the thrust and torque coefficients. The minimum iteration number and grid density are carefully chosen to reduce the computational effort required. The velocity field behind the ship is recalculated into an effective wake and given to the propeller code that calculates the propeller load. Once the load is known it is transferred to the RANS solver to simulate the propeller action. Knowledge on the propeller behavior and the impact of improvements in hull and propeller geometries introduce valuable new perspectives for hull design.