Research On Acoustoelectric Transducer System Based On Coupled Helmholtz Resonator

With the depletion of traditional petrochemical resources and the continuous development of new clean energy,research on energy utilization in recent years focuses more on the collection of potential energy available in the environment,including mechanical energy,solar energy,thermal energy,tidal energy,biomass energy and sound energy,etc.Compared with other energy sources,sound energy is widely distributed,such as tunnels,railways,airports,highways,large shopping centers,factories and other environments have a lot of noise.In daily life,high decibel noise will affect People's Daily life and health,therefore,noise control and sound energy collection and use is particularly important.In addition,unlike the new clean energy such as light energy,heat energy and solar energy,sound energy is not restricted by natural conditions such as location and weather.Therefore,it has a broad application prospect to directly convert sound energy into electric energy by using the acoustic-electric energy exchange system for the power supply of low-power miniature electronic equipment.In order to effectively collect the noise in the environment,an acoustic-electric energy transfer system is proposed.The system consists of coupling Helmholtz resonator elements.The piezoelectric composite is attached to the wall between the two coupling cavities,and the sound energy can be converted into electric energy by using the positive piezoelectric effect of the piezoelectric material.The main research contents and innovations of this paper are as follows:1.Based on the theory of equivalent circuit and the knowledge of basic acoustics,two new types of acoustic energy collecting structures based on the coupled Helmholtz resonator element are designed.One is the coupled Helmholtz resonator structure with an extended neck in the cavity,and the other is the coupled Helmholtz resonator structure with an inclination Angle at the bottom.2.Established two new type coupling finite element model of Helmholtz resonator sound energy collection system and the cavity acoustic pressure distribution carried on the thorough analysis,compared under the condition of the same volume,and the bottom of the cavity with extended neck with dip Angle structure and flat type coupling of Helmholtz resonator type coupling structure of Helmholtz resonator sound pressure distribution and the characteristics of power generation.At the same time,the influence of the geometric parameters on the output voltage of the acoustic energy collector was studied by changing the geometric parameters of the extension neck,the inclination Angle of the bottom and the piezoelectric vibrator by the control variable method.The simulation results show that the internal extension neck can adjust the resonant frequency and increase the output voltage of the coupled Helmholtz resonator.Is at the bottom of the slope Angle of the coupling type of Helmholtz resonator,the adjacent two cavity pressure phase opposite,bonding between the two cavities on both sides of piezoelectric composite patches on the wall at the same time by opposite pressure caused by push pull together,compared with no Angle at the bottom of the flat coupling of Helmholtz resonator,the coupling of Helmholtz resonator with dip Angle at the bottom of the sound reflection effect near the piezoelectric vibrator has a greater density of sound pressure,the higher output voltage.3.Made the coupling type of Helmholtz resonator with dip Angle at the bottom of the sound energy at the bottom of the collector and no inclination of sound energy collector type coupling of Helmholtz resonator physical model,using the impedance analyzer and standing wave tube to sound energy collection system has carried on the experiment of the electricity generating performance tests,and the experimental test results with finite element simulation results were compared.The results show that the experimental results are basically consistent with the finite element simulation results.The inclination Angle at the bottom of the coupled Helmholtz resonator can increase the sound pressure near the piezoelectric vibrator,so as to improve the output voltage of the acoustic energy collector and solve the problem of low efficiency of the piezoelectric acoustic energy collector.