BEM-FEM coupling for the hydroelastic analysis of propeller-shafting systems in non-uniform flows

Abstract

The understanding of the fluid-propeller-shafting system's hydroelastic behavior is critical for underwater vehicle vibration and noise reduction. A three-dimensional panel method coupled with a three-dimensional finite element method for analyzing the hydroelastic dynamics of fully coupled propeller and shafting systems in the non-uniform flows is developed. The fully coupled fluid-propeller-shafting model is utilized to assess the applicability of the traditional uncoupled fluid-propeller (elastic vibration)/fluid-propeller (six degrees rigid body oscillation)-shafting models, which consider the elasticities of the blades and shaft separately. It is found that the designers need to consider the elastic coupling effect between the shaft and the propeller, especially in the case of high skew propellers. In addition, the uncoupled model underestimates the fluid-induced damping.