Vibration and noise analysis method of marine gear transmission including the base admittance characteristics

A method which can include the base admittance characteristics accurately and effectively in vibration and noise analysis of marine gear transmission is proposed in this paper. This method is introduced by taking a sing-stage double helical gear transmission as an example. The accuracy of physical parameter identification method based on skeleton line is verified by taking a two degree of freedom system as an example firstly. Then according to the self-admittance curve of base at the connection points to gearbox, the base is taken as three two degree of freedom systems at each connection point. The physical parameter of each system is identified using skeleton line method. And then the vibration and noise analysis model is constructed by simulating each two degree of freedom system using mass elements and spring elements. Based on this model, the vibration and noise is analyzed by taking the bearing dynamic loads which are obtained by solving gear dynamic formulations as excitation. Finally, the experiment is conducted to validate the accuracy of the method proposed in this paper. The results show the vibration and noise analysis results become more accurate after including the base admittance characteristics. The difference between simulated and measured structural noise and radiated noise does not exceed 4.5 dB.