CFD-FEM Analysis of Flow-Induced Vibrations in Waterjet Propulsion Unit

This paper investigates the problem of vibration in an axial flow waterjet propeller with high power density and low specific speed. Based on fluid-structure coupling vibration analysis, combined with modal analysis and ship tests, the unsteady fluid-structure coupling of a waterjet propeller is examined, and the vibration characteristics of the propeller under different speed conditions are studied. The results show that the vibrations of the waterjet propeller mainly come from the frequency response of the rotor and the structural resonance response. The frequency distribution characteristics and amplitude intensity are observed to increase with increasing rotation speed. The variations in the propeller vibration characteristics, with respect to parameter changes, are analyzed at different gap spacings between the rotor and stator, allowing the variation law of vibration intensity with rotor stator spacing to be obtained.

Automated summary

This paper investigates the vibration problem in a high power density and low specific speed axial flow waterjet propeller. By utilizing fluid-structure coupling vibration analysis, modal analysis, and ship tests, the study examines the unsteady fluid-structure coupling of a waterjet propeller and investigates the vibration characteristics under different speed conditions. The results indicate that the vibrations mainly originate from the rotor's frequency response and structural resonance response. Both frequency distribution characteristics and amplitude intensity increase with higher rotation speeds. The study also analyzes the variations in the propeller vibration characteristics with respect to changes in the gap spacings between the rotor and stator, leading to the identification of the variation law of vibration intensity with rotor-stator spacing.