Experimental and Simulation Study on Vibration Transmission Characteristics and Vibration Isolation Effect of a New Floating Raft Vibration Isolation System

In order to improve the vibration isolation effect of the floating raft vibration isolation system, a new experimental platform for floating raft vibration isolation with two stiffnesses was built. First, the mathematical model of the vibration isolation system was established. The vibration transfer function of the vibration isolation system was deduced by using the substructure derivative synthesis method and the four-end parameter matrix method. The transfer function under the structural parameters was calculated, and the influence of structural parameters on the vibration transfer function was analyzed. Then the floating raft modal test was carried out and the three-dimensional finite element model of the floating raft vibration isolation structure was established. The finite element analysis results were compared with the test results to verify the validity of the finite element model, and then the vibration characteristics of the support structure were studied. Finally, by measuring the acceleration responses at the upper and lower ends of the isolator, the difference is taken as the evaluation index of the vibration isolation effect to investigate the isolation effect of the isolator under the conditions of on-land and underwater usage, and to preliminarily explore its influence on the underwater acoustic radiation of the device. The results demonstrate that the vibration isolator with two stiffnesses can reduce the vibration transmission within a specific frequency range in both on-land and underwater application scenarios, which holds guiding significance for the research of vibration isolation technology in practical engineering.