Numerical simulation of structural response during propeller-rudder interaction

Abstract

The propeller wake can cause vibrations on the rudder surface, which worsen the noise and reliability. The vibration monitoring of the rudder operating in the propeller wake with fluid-structure interaction (FSI) method is still challenging. In the present study, the structural response during propeller-rudder interaction is investigated using detached eddy simulation. Three-dimensional distributions of loads, stresses, and deformations are discussed. The leading and trailing edges exhibit the strongest deformations in opposite directions, which are S-shaped. The strongest lateral deformation occurs between the tip vortex and hub vortex regions. In the tip vortex region, the dominant lateral vibrations fluctuate at the blade passing frequency (BPF) and shaft frequency (SF). However, the 75 Hz-fluctuation becomes significant at the trailing edge of the rudder. In the hub vortex region, the lateral deformation fluctuates mainly at 75 Hz except the area near the leading edge. There are weak vibrations occurring at the natural frequencies of the rudder when the natural frequencies of the rudder are much higher than the SF and BPF. However, the plate in the propeller suffers intense vibrations at the frequencies near the natural frequencies, where the natural frequencies of the plate are close to SF and BPF.