Isolation And Shock Response Characteristics Research Of Floating Raft System In Ships

Controlling the vibration and noise in ship is always playing the important role in the theoretic and practical research of vibration isolation. The ship structural oscillatory issue arose from the dynamical mechanics is the emphases of the engineering research all the while. With the development of technology, the higher and stricter requests on the capability of the vibration isolation system are brought forward. To some extent, the traditional double-stage vibration isolation instrument can hardly meet the expectations. The floating raft oscillation isolation system developed in recent years is an effective instrument to ship dynamical mechanics to implement the isolation of noise and vibration.In this paper, the basic theory of vibration control will be introduced first, and vibration-isolating common problems are proposed analyzed and calculated, and the concept of marine floating raft vibration-isolating system is described, also the model-buliding method was described in detail, and the dynamic differential equation is induced with particular interest. The modal frequency of the Marine floating raft are calculated by the code presented in this paper, and the result is compared with the result obtained from FEM method calculation. The present method was proved by the comparation. The transfer frequency response function at nodes of the Marine floating raft are calculated by harmonic response method, vibration level difference was also calculated at some presentative nodes.The shock-resistant and analysis method of onboard equipments is discussed. The U.S Naval DDAM(Dynamic Design Analysis Method)is reviewed in detail. Using ANSYS the model of marine floating raft vibration isolating system was made. By making program, the natural frequency was calculated. The results are in accord with the results using ANSYS. The simulating model accords with the real model. The shock response of a marine floating raft vibration isolating system is calculated and analyzed based on the U.S. Naval rule DDS100-7.The calculation and analysis method that was used in this paper can also be used to analyze the shock-resistant performance of naval onboard equipments.At last, the modal experiment of the marine floating raft system was made, after marking value by measuring system, transducer were re-marked in particular which lose the marked value previously, after obtaining the marked value, the modal analyze of the marine floating raft with different thick was made by single input and multi-output modal analyze method...