Investigation of the flow field around a propeller-rudder configuration: on-surface pressure measurements and velocity-pressure-phase-locked correlations

The present paper deals with the problem of the propeller induced perturbation on the rudder . The study aims at providing insights on the key mechanisms governing the complex interaction between the propeller wake structures and the rudder. In this regard, a wide experimental activity that concerned PIV and LDV velocity measurements and wall-pressure-measurements on the two faces of the rudder was performed in a cavitation tunnel. The major flow features that distinguish the flow field around a rudder operating in the race of a propeller, were highlighted, such as the complex dynamics of the propeller tip votices and the re-storing mechanism of the tip vortex downstream of the rudder. Wall-pressure signals were Fourier decomposed and, then, reconstructed isolating the contributions of the more energetic harmonics when both the propeller phase and the rudder deflection change