FSI Analysis of a Marine Rudder Behind a Propeller

The dynamic response of a marine rudder located in the wake of a propeller is analyzed by the one-way fluid structure interaction (FSI) approach. The time-dependent loads on the rudder are obtained through detached eddy simulation and are used as input for a structural solver to determine the resulting deformations and stresses. The computations consider the propeller at moderate loading and rudder deflection angles at neutral and ±4°. The structural response of the rudder is dominated by lateral and torsional deformations, whereas the edgewise deformations are negligible. The lower frequency vibrations are linked to the hydrodynamic interaction with the propeller wake, whereas the higher values are ascribed to the rudder natural mode of vibrations. Moreover, the study includes the identification of the specific contribution of the tip and hub vortex to the rudder deformation.