Transfer Path Analysis of Structural Vibration on Propulsion Motor

Abstract

Reduction of vibration noise of propulsion motor, which is the main excitation source of ships, is of great significance for improving the acoustic stealth performance of ships. An established motor feet vibration transfer path analysis (TPA) model is used to determine the primary excitation source and transfer path. Hammering method is used to test the transfer function of the path and collect the response of reference and target points in the operation conditions. The TPA is carried out based on the experiment to identify the equivalent exciting force and to calculate the path contribution amount. The results show that in the frequency range of 1-1000 Hz, the vibration acceleration-level error of the synthetic response and the measured response is <;3 dB, and hence the model is accurate and reliable. Recognized equivalent excitation force can be used for the simulation of excitation load. Contribution analysis results indicate the direction for structural improvements that have practical value.