Optimized Design of Ship Damper Matching in Ice Area Based on NSGA-III

Torsional vibration is a common form of vibration of ship shaft system. Such torsional vibration can be more severe when the ship sailing in the polar region due to the excitation of ice load. This study takes a shaft system as the object of research and proposes a method of optimizing the design of the silicone oil damper based on the dynamic analysis of the ship's shaft system to reduce the torsional stress of the shaft system in the icy areas. Models of the coupled system dynamic model of the silicone oil damper, the shaft system, and the propeller are first established. Newmark-β method is used to solve the system dynamic response numerically. Based on the dynamic response of the shaft system, a multi-objective genetic optimization algorithm is used to match the optimized design of the damper. The results show that the optimized silicone oil damper makes the torsional vibration stresses of the motor shaft, motor shaft, and propeller shaft decrease. Based on the dynamics response of the shaft system, a multi-objective genetic optimization algorithm is used to match the optimized design of the damper. The results showed that the optimized silicone oil damper resulted in a reduction of torsional vibration stresses of the motor shaft, intermediate shaft and propeller shaft by 18.0%, 11.8% and 17.7%, respectively.