Aiming to study the effect of flexible support propulsion system on the vibration noise of paddle-shaft-boat coupling system. A numerical model of the flexible support propulsion system-hull coupling system is established, and the vibration and radiated noise of the hull under the longitudinal, horizontal and vertical excitation of the propeller are calculated by using finite element/boundary element method, and compared with the traditional support system. The results show that the larger radiation noise of the boat body is mainly caused by the coupling mode of shafting and raft frame, and it is beneficial to reduce the radiation noise of the boat body by improving the mass and stiffness of raft. Compared with the traditional support, the flexible support can significantly reduce the radiated noise of the boat body, which can reduce 14.65dB under the longitudinal excitation,4.48dB under the horizontal excitation, and 8.36dB under the vertical excitation. The use of flexible support propulsion system can reduce the hull radiated noise and provide support for vibration and noise control of propeller-shaft-hull coupling system.
