Vibration Analysis And Vibration Reduction Technology Research Of Marine Cabin Walls

A ship's cabin is a general term for all enclosed spaces separated by Longitudinal and transverse bulkheads and decks.Due to the numerous sources of excitation on board(main engines,auxiliary engines,propellers,pumps,Air compressor,air conditioners,etc.)causing the ship's cabin to vibrate excessively.Excessive cabin vibration will affect the performance of the ship and the comfort of the ship.Therefore,the cabin damping is an important research topic of modern ships.Viscoelastic constrained damping materials can reduce vibration and noise in a wide frequency band.ASPHALT,soft rubber and polymer materials can be classified as common viscoelastic constrained materials.Viscoelastic constrained damping material is composed of polymer,which has two characteristics: Energy consumption of viscous liquid and energy storage of elastic solid.When the viscoelastic constrained damping material is impacted by the external load,the heat generated on the one hand is consumed and the energy not consumed on the other hand is stored in the form of potential energy.In this paper,the damping material with viscoelastic constraint is used to reduce the vibration of the bulkhead.Firstly,a scaled model of a real ship is taken as the research object,and the natural frequencies and vibration modes of the cabin are obtained by finite element analysis,the accuracy of the finite element model is verified.Secondly,the finite element model of viscoelastic constrained damping materials is established,and the harmonic response analysis of viscoelastic constrained damping materials and non-viscoelastic constrained damping materials is compared,the damping effect of viscoelastic constrained damping material is obvious.Thirdly,the finite element model of viscoelastic constrained damping material laid on one side is established,the modal analysis is carried out,the loss factor is calculated,and it is found that the effect of vibration reduction by laying on one side is close to that of laying on the whole side,in order to further study the influence of laying area,laying thickness and material parameters on the vibration of composite structures,based on the finite element method,the effects of the change of young's Modulus,the change of thickness and the change of the area of the damping layer on the natural frequency and loss factor of the composite structure are calculated,the effects of the above factors on the vibration reduction are obtained.Finally,the test method and the test system are introduced,and the test results are compared with the simulation results.