Research On Vibration And Noise Reduction Performance Of Two-Dimensional Three-Component Phononic Crystal Plate Based On Polyurethane

The rapid development of science and technology has greatly promoted social progress,followed by increasing noise pollution.The vibration and noise reduction materials of traditional structures are mainly composite structures with high density and high hardness,and often only aim at the noise with high frequency,while the noise with low frequency becomes ineffective.Therefore,it is of great significance to study the new lightweight low-frequency composite structure.In this paper,polyurethane material is selected as the cladding layer of the composite structure to form a resonant structure with metal vibrator.The resonant frequency affecting the resonant structure is discussed from the density and shape of vibrator and the thickness of polyurethane layer;The influence of the resonant frequency of the resonant structure and the vibration damping performance and sound insulation performance of the periodic structure is discussed:Firstly,using metal vibrator,polyurethane elastomer and epoxy resin plate as raw materials,taking the density,shape and thickness of polyurethane layer of vibrator as single variables,three resonance structures with different parameters were prepared by die forming.Secondly,the mechanical properties of resonators with different densities and shapes and resonant structures with different cladding thickness are tested.The resonant frequency of the resonant structure is approximately calculated from the compression modulus of the resonant structure,and then the resonant frequency of the resonant structure is further determined by using the frequency of the peak value of the damping loss factor,so as to explore the influence of structural parameters on the resonant frequency of the resonant structure.The results show that the resonant frequency of the resonant structure decreases with the increase of oscillator density;The shape of the oscillator has no effect on the resonance frequency;When the polyurethane layer thickness increases,the resonance frequency of the resonant structure decreases and the damping loss factor tanδ of the resonant structure decreases the higher the curve.Finally,the sound insulation performance and vibration damping performance of phononic crystal plates with different density,different shape,different number of cycles and different coating thickness are tested.The results show that the above four factors have a certain impact on the vibration and sound insulation performance of the composite structure.The periodic structure can be designed by selecting appropriate parameters according to the required sound insulation frequency band and vibration reduction frequency band.This paper lays the foundation for the application of this kind of resonant structure in the field of vibration reduction and noise reduction.