Analysis and prediction of vibro-acoustic characteristics of parallel propulsion systems for large-scale marine ships

The parallel power propulsion system is the preferred option for large-scale ships. The improper configuration of multidimensional power parameters is a significant factor contributing to the vibration and noise generated by the system. This study examines the sensitivity and dependence of the vibro-acoustic characteristics of the system on various power parameters through theoretical and experimental methods, and reveals the evolution mechanism of the dynamic behaviors under the coupling effect of multidimensional power parameters. Firstly, the nonlinear dynamic model considering the lateral–torsional–axial coupling of the propulsion system is established and the effects of different combinations of power parameters on the vibration response and system stability are investigated. Secondly, an experimental platform of the parallel propulsion system is constructed, and the comprehensive description of the effects of multidimensional power parameters on the vibration and noise of the system under asymmetrical input power is further provided. Finally, the radial basis function (RBF) neural network is innovatively employed to predict and approximate the vibro-acoustic characteristics of the system under the combined influence of rotating speed, torque ratio, and drag current. The research results are of significant theoretical and practical importance in breaking through the technical bottleneck related to reducing the vibration and noise of such parallel propulsion systems.