Research On Vibration Isolation Performance Of Metal Rubber Floating Raft Under Multi-frequency Coupled Vibration

With the progress of modern industrial technology,people’s requirements for vibration isolation of daily equipment and environmental comfort requirements are increasing,especially in the production environment,multiple vibration sources in the elastic base caused by the multi-frequency coupling vibration problems seriously affect the safety and normal use of equipment.For multi-frequency coupled vibration,the traditional single layer vibration isolation cannot meet the requirements of vibration control due to the limitations of space and foundation.Floating raft,as an important means of coupled vibration control,is widely used in the coupled vibration control of large vibration equipment such as naval units and offshore oil platforms.In this paper,according to the design criterion of the floating raft system,the dynamic model of the metal rubber floating raft isolation system under coupling excitation is established by using the four-terminal parametric derivative matrix subsystem synthesis method,and the theoretical model was numerically simulated by MATLAB.The effect of the structural parameters of the floating valve vibration isolation system on the vibration characteristics was studied by the power flow analysis method.Changing the stiffness of the vibration isolator can change the magnitude of the power flow transmission rate and the natural frequency of the system,increasing the stiffness of the lower vibration isolator and decreasing the stiffness of the upper vibration isolator are beneficial to the vibration isolation performance of the system.The characteristics of direct vibration isolation are compared with those of metal rubber floating raft,which shows that the raft plays an important role in vibration isolation.Comparing the vibration characteristics of the system with single and multiple vibration sources,it is shown that the coupled vibration of multiple vibration sources can improve the vibration isolation ability of the floating raft system.Comparing the different placement of vibration isolators,it shows that the change of the position of the lower vibration isolator affects the vibration isolation ability.A metal rubber floating raft vibration isolation test rig was built to test the vibration parameters of each position under different harmonic excitation generated by two shakers,and the vibration isolation performance of the float valve was verified.The comparison between the test power flow curve and the simulation curve proves the rationality of the dynamic model.In this paper,according to the viscoelastic characteristics of metal rubber,the restorative force model of metal rubber is optimized,the hysteresis curve is fitted by the method of parameter identification,the equivalent stiffness and damping are calculated,and the vibration isolation ability of the floating valve system under the coupled harmonic excitation is obtained.This paper proposes and metal rubber raft system is established,through numerical simulation combined with vibration isolation test methods to analyze the metal rubber vibration isolation of vibration of multiple frequency coupling floating raft system performance,and through constructing test rig,vibration isolation performance of the test methods to verify the metal rubber vibration isolation materials in multiple frequency coupling vibration system of effectiveness and feasibility of theoretical significance and practical value.