Contribution of tip and hub vortex to the structural response of a marine rudder in the propeller slipstream

The structural design of the rudder, traditionally based on quasisteady loads generated during worst manoeuvres, should account for load fluctuations associated with the interaction with the wake of the propeller in order to comply with the more stringent requirements on ship vibration and noise pollution. In this context, the present work analyses the dynamic response of a marine rudder located in the wake of the INSEAN E779A propeller by the one-way fluid-structure interaction approach. The time-dependent pressure distribution on the rudder, obtained through detached eddy simulation, is used to evaluate the pressure field that is the 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 degrees. The analysis discusses the different contribution of the tip and hub vortex of the propeller on the static and vibratory response of the rudder in the two configurations.