Axiomatic Design Of Vibration Isolation And Shock Resistance For Floating Raft System For Ship's Power Propulsion Unit

Ship's power propulsion unit is the most important power source for ships. The good vibration isolation performance of the floating raft system is very important to improve the reliability of the ship. The good shock resistance of the floating raft system can make the ship avoid the failure of the propulsion device under the harsh impact environment. Therefore, the floating raft system used for ship's power propulsion system must both have good vibration isolation and shock resistance performance. However, the existing floating raft system design does not meet this requirement.Firstly, based on axiomatic design theory, the vibration isolation design, the shock resistance design, both vibration isolation and shock resistance design of the floating raft system are analyzed. It is found that the existing design problem of the floating raft system can not satisfy the good vibration isolation and shock resistance performance. The main reason is that the stiffness design of the lower isolators couples. In order to reduce the coupling degree of the lower vibration isolators, the stiffness of each vibration isolator of the lower vibration isolators is redistributed. With the finite element method, the vibration isolation of the lower vibration isolators is taken as the vibration isolation evaluation index, and the displacement response of the diesel engine is taken as the shock resistance evaluation index. The lower vibration isolators of the floating raft system are designed.The results show that the vibration isolation and shock resistance performance of the optimized raft system are obviously improved compared with the existing design. The results of the axiomatic design analysis and the proposed decoupling scheme are correct. This provides some guidance for the stiffness design of the lower vibration isolators of the floating raft system.