Research On The Characteristics Of Low Frequency Vibration Suppressor And Parameter Analysis

Suppressing the vibration and noise radiation of a ship in water is of great significance to improve the life of the mechanical equipment on the ship,improve the comfort of the staff and enhance the acoustic stealth performance of the ship.The low-frequency vibration suppressor is a new form of low-frequency vibration suppression equipment,which has a good effect on the vibration and noise of the structure in the low frequency range.In order to analyze the suppression characteristics of low-frequency vibration suppressors on low frequency vibration and noise of underwater structures,In this paper,based on the finite element analysis method,a sound and vibration simulation analysis model of the underwater plate structure with low-frequency vibration suppressor attached is established.And then,the vibration and noise reduction effect and mechanism of low-frequency vibration suppressor are analyzed,the parametric of it is analyzed,and the characteristics of multiple low-frequency vibration suppressors and low-frequency vibration suppressor arrays are analyzed.First,the related theory of solving the underwater plate mean square vibration velocity and radiated sound power is introduced,the FEM of acoustic and vibration characteristics of underwater simply supported plate structure is established.Compare FEM results with theoretical solutions to verify that the finite element simulation method can accurately predict the acoustic characteristics of a simply supported underwater plate.On this basis,the acoustic vibration characteristics of the underwater additional mass load plate,the underwater attached mass plate and the underwater stiffened plate are simulated in turn,Compare FEM results with theoretical solutions to verify the finite element simulation method can accurately predict the acoustic and vibration characteristics of underwater plate with additional structure.It lays the foundation for the subsequent acoustic and vibration simulation analysis of the underwater flat-plate structure with low-frequency vibration suppressor attached.Secondly,the simulation analysis model of the acoustic vibration characteristics of a simply supported underwater flat plate with a low-frequency vibration suppressor attached is established.And then,Analysis of the effect and mechanism of vibration and noise reduction of low-frequency vibration suppressor in the low frequency range.The effects of material parameters and structural parameters,such as loss factor,Young’s modulus,top mass,height,cavity,etc.,on the vibration and noise reduction performance of the lowfrequency vibration suppressor analyzed.The research results can provide a reference for the design of low-frequency vibration suppressors in practical engineering applications.Finally,the suppression effect of low-frequency vibration suppressor on vibration transmission is analyzed.On the basis of,For the situation of use multiple low-frequency vibration suppressors,and according to the vibration transmission direction,two arrangements of the vertical vibration transmission direction and the vibration transmission direction are proposed,then analyze the advantages and disadvantages of the two arrangements and the impact of the installation location on the vibration and noise reduction effects of the two arrangements.In the meantime,The vibration and noise reduction characteristics of the low-frequency vibration suppressor array are studied,and the effects of array arrangement density and array form of arrangement are analyzed.