Finite Element Simulation And Experimental Study Of Flow-induced Piezoelectric Energy Harvester With Magnetic Clinder Bluff Body

Piezoelectric vibration energy harvester is based on the piezoelectric effect to convert the vibration energy in the environment into electric energy.It has the advantages of high energy density,fast response,long life,no pollution,simple structure and easy integration into microelectronic systems,etc.The power supply of low-power electronic products such as electronics,MEMS,and micro-sensors is one of the hot topics in the study of dynamics and control disciplines.The fluid-induced vibration piezoelectric energy harvester is a fluid-solid-electricity coupling system that generates vibration by fluid-structure interaction in the fluid and further uses piezoelectric effect to realize energy conversion.How to improve the energy conversion efficiency and the adaptability of the environment,the dynamic characteristics analysis of the energy capture structure is the key.In this dissertation,a novel flow-induced vibration-enhanced piezo-electricity piezoelectric energy harvester based on the theory of flow-induced vibration and the basic research of piezoelectric vibrators based on current vibrations is designed.The principle of fluid eddy-vibration and piezoelectric effect are used to collect electrical energy.The effects of flow velocity,diameter of fluid,magnetic spacing,and magnetic pole on the vibration frequency of the energy harvester are numerically analyzed;the characteristics and flow of the piezoelectric field energy of the piezoelectric energy capture device are simulated by finite element simulation.The influence of the field on the piezoelectric energy harvester;experimental analysis of the flow rate,magnetic spacing,magnetic pole,piezoelectric layer length and the shape of the fluid around the piezoelectric energy harvester energy harvest performance.The research content of the paper mainly includes the following three parts:(1)Analysis of the natural frequency of the magneto-encapsive piezoelectric energy harvester: The natural frequency of the energy capture device is calculated using the mechanical vibration theory,and the influence law of the length of the base layer and the fluid mass on the natural frequency of the energy capture system is analyzed;the theory of vortex shedding is used.The eddy-induced frequency of the fluid-induced vibration is calculated,and the effects of different flow velocities and diameters around the fluid on the vibration frequency of the energy harvester are analyzed.The frequency-sweeping experimental study of the magneto-encapsulated piezoelectric energy harvester is conducted to analyze the magnetic spacing and the arrangement of the magnetic poles on the piezoelectric energy capture.The effect of the natural frequency of the device.(2)Fluid-Solid Coupling FE Finite Element Simulation Analysis of a Piezoelectric Piezoelectri Energy Harvester: In the flow field,the structure is excited by the flow field to generate vibration and influence the flow field velocity distribution,vortex distribution,and pressure distribution.The main content of this paper is to study the flow-induced vibration response of the structure of the energy harvester.Finite element simulation analyzes the displacement,strain,stress,output voltage,and electric field strength of the energy harvester at different flow rates.(3)Experimental study of magneto-encapsive piezoelectric energy harvester: an experimental system for studying the underwater energy harvesting characteristics of magneto-encapsulated piezoelectric energy collectors is introduced,and experimental platforms,experimental fixtures,and experimental components are introduced;Around the fluid structure,the influence of the flow velocity,magnetic spacing,magnetic pole and piezoelectric layer length on the energy capture performance of the piezoelectric energy harvester was analyzed;a detailed comparison was made between a fluid with a circular cross section and a fluid with a square cross section and a D-shaped rear circular cross section around the fluid.The difference of energy capture effect of piezoelectric energy traps in water;experimental comparison and analysis of the influence of front circular section and back circular section of D-shaped fluid on piezoelectric energy harvester;finite-element and experimental comparison analysis of different round-round fluids Piezoelectric energy harvester energy capture characteristics.