Research On Energy Recovery Device Of Pneumatic System Based On Piezoelectric Effect

As one of the important means of production automation,pneumatic system is widely used in various production workshops.However,its energy utilization ratio is lower than that of electrical system and hydraulic system,so pneumatic system still has a great space for energy saving.In the pneumatic system,compressed air after finish work usually empty,without any processing caused the waste of energy,the traditional exhaust recycling method can produce back pressure,the normal operation of the pneumatic system,and based on the piezoelectric effect of energy recovery device small impact on the system,and has a simple structure,high energy conversion rate,no pollution,etc.The capture of fluid energy by piezoelectric energy harvesters has become a research hotspot.However,because aerodynamic exhaust is impingement jet,the traditional flow-induced vibration piezoelectric energy harvesters cannot produce complete flow around phenomenon.Therefore,it is very necessary and urgent to study the piezoelectric energy harvesters suitable for pneumatic exhaust recovery.The research work of this paper mainly includes the following aspects:(1)The aerodynamic characteristics of exhaust air are analyzed,and a structural scheme of piezoelectric energy harvester device consisting of an open semicircle-cross-section spoiler and a flexible piezoelectric cantilever beam is proposed.On this basis,the mechanism of energy harvester is analyzed,a fluid-solid-electric three-field coupling mathematical model is established,and the key parameters affecting the output performance of the device are determined.(2)Based on the theoretical analysis,the numerical analysis of the piezoelectric energy harvester device is carried out,the influence of the spoiler column on the first natural frequency of the device is studied through modal analysis,the influence law of key parameters on the amplitude of the device is studied by using the two-way fluid-solid coupling method,and the structure size of the device is preliminarily determined.(3)Based on theoretical analysis and simulation results,a test prototype is made,a test platform is built,the simulation results are verified,and the influence of the spoiler column on the output characteristics of the captor and the influence law of load resistance on the output voltage and power are studied.The experimental results show that the first natural frequency of the device can be greatly reduced by the spoiler,and the maximum output voltage can be increased by 4.2 times.When the exhaust pressure is lower than this pressure,the vibration of the absorber is not obvious.When the exhaust pressure is reached,the amplitude of the absorber suddenly increases and increases with the increase of exhaust pressure.In turbulence column to vent distance is 100 mm,disturbed flow column 10 mm diameter,under the condition of the prisoner can under the exhaust pressure of 80 k Pa to achieve the maximum output voltage of about 35.4 V,is the best load resistance of 11m?,makes the maximum output power of 93.7?W.The research results of this paper will provide a new way of energy supply for low energy consumption devices in pneumatic systems.