Topology Optimization Research And Vibration Characteristics Analysis Of The Floating Raft Isolation System

With the improvement of stealth performance of modern ships,and the need of comfortable working environment,the floating raft vibration isolation system has been applied more and more widely,which plays an important role in vibration and noise reduction of ship equipment.Therefore,it is of great value to analyze and study the floating raft vibration isolation system.Aiming at the structural topology optimization technology,this paper adopts the variable density method to establish its mathematical model,deduces the algorithm of topology optimization criteria based on SIMP,conducts the topology optimization weight reduction analysis of the floating raft vibration isolation system based on the variable density method,and designs the final optimized raft structure.Then,the finite element model of floating raft vibration isolation system is established,including the modeling of upper unit,middle raft body,lower foundation and upper and lower vibration isolator.By analyzing the harmonic response of the floating raft isolation system,the response data of its nodes under a given load is obtained.The vibration transfer characteristics of the floating raft vibration isolation system were studied by using the analysis method of power flow transfer,and the power flow transfer curve was drawn.The results show that there is little difference in the vibration isolation effect of the raft before and after optimization,but the weight of the raft is greatly reduced,and the structure of the raft is well optimized.Next,this paper designs and processes the optimized intermediate raft body in detail,and assemblies and connects the vibration motor,upper frame,intermediate raft body,lower foundation and air spring and so on,building the whole floating raft vibration isolation experimental system.Then according to the measurement of the vibration acceleration of measuring points and draw out of the floating raft isolation system vibration acceleration level curve in each layer,the results show that the vibration isolation effect of air spring is closely related to its stiffness,and the floating raft vibration isolation system has an excellent vibration isolation performance.Finally,the frame floating raft structure,which is widely used in naval ships,is optimized and analyzed with the research method of this paper,the calculation shows that the optimized structure has good vibration isolation effect.In this paper,the structural optimization method and vibration characteristic analysis method of floating raft isolation system can provide technical support for the optimization design of practical engineering structures.