Analysis And Experimental Research On The Performance Of Electric Energy Generated By Airflow-induced Acoustic Piezoelectric System

With the development of weapon system and the expansion of fuze function,the requirement of fuze power supply is higher and higher.As a new type of fuze power supply,airflow acoustic generator has no moving parts,so it has many advantages,such as small size,light weight and so on.The generation technology of airflow induced acoustic piezoelectric energy is a new technology developed in recent ten years,which is a kind of airflow induced acoustic energy conversion mechanical technology.Based on the principle prototype of airflow acoustic generator,this paper further analyzes the power generation performance of the system and optimizes the structure parameters,so as to ensure the maximum power output and lay a foundation for future engineering design and application.Based on the working principle of airflow induced sonic generator and the mechanism of electric energy generation,an equivalent acoustoelectric model is established.The law of output voltage and displacement under the maximum output power of the resonant state is analyzed.The experimental results show that the nozzle-resonator sound tube is insensitive to the external flow disturbance and has good robustness,and the output voltage and the piezoelectric oscillator shift at the same frequency and close to the acoustic pressure excitation signal frequency,which verifies that the generator operates in the resonant state.Based on the analysis of the fuze application environment,the velocity of the projectile is calculated by numerical simulation,and the structure of the concentrated air inlet is designed.The power supply control scheme controlled by the fuze environment is proposed.The influence of the structural parameters of the piezoelectric actuator on the amplitude characteristics of sound pressure is studied by orthogonal experiment.The optimum parameters of annular gap,resonant cavity length and spacing are A₂B₃C₂.The annular gap,resonant cavity length and spacing are 1,10 and 3(mm)respectively.The results show that the resonant frequency of the piezoelectric transducer is proportional to the square of the radius,and is inversely proportional to the total thickness,and the electromechanical coupling coefficient is larger.The results show that the structure is intact and can generate electricity normally under the condition of more than 15000g continuous hammering,which can meet the requirements of overload resistance of fuze application.The test results show that the prototype can generate electricity normally and meet the technical requirements of working environment temperature after 6 hours of heat preservation at-40?and 50?.After 82mm mortar 0,1,2,3 charge firing test,recovery test results show that the generator has a continuous output voltage signal,which proves that the generator can generate electricity in flight,verifying the feasibility of application in fuze.