Modeling and Analysis of Upright Piezoelectric Energy Harvester under Aerodynamic Vortex-induced Vibration.

Jinda Jia,Rujun Song,Yaowen Yang,Deepesh Upadrashta,Tao Xie,Xiaobiao Shan

doi:10.3390/mi9120667

Abstract

This paper presents an upright piezoelectric energy harvester (UPEH) with cylinder extension along its longitudinal direction. The UPEH can generate energy from low-speed wind by bending deformation produced by vortex-induced vibrations (VIVs). The UPEH has the advantages of less working space and ease of setting up an array over conventional vortex-induced vibration harvesters. The nonlinear distributed modeling method is established based on Euler–Bernoulli beam theory and aerodynamic vortex-induced force of the cylinder is obtained by the van der Pol wake oscillator theory. The fluid–solid–electricity governing coupled equations are derived using Lagrange’s equation and solved through Galerkin discretization. The effect of cylinder gravity on the dynamic characteristics of the UPEH is also considered using the energy method. The influences of substrate dimension, piezoelectric dimension, the mass of cylinder extension, and electrical load resistance on the output performance of harvester are studied using the theoretical model. Experiments were carried out and the results were in good agreement with the numerical results. The results showed that a UPEH configuration achieves the maximum power of 635.04 μW at optimum resistance of 250 kΩ when tested at a wind speed of 4.20 m/s. The theoretical results show that the UPEH can get better energy harvesting output performance with a lighter tip mass of cylinder, and thicker and shorter substrate in its synchronization working region. This work will provide the theoretical guidance for studying the array of multiple upright energy harvesters.

Highlights

With rapid development technologies, such as portable electronic devices, micro electro mechanical systems (MEMS) and wireless sensors, the reliance on the traditional battery has become a major obstacle due to expensive replacement, bulky volume, limited lifetime, and time-consuming maintenance
The results showed that the T-shape piezoelectric energy harvester (TPEH) whose cylinder was perpendicular to the beam should be operated at higher wind speed while the upright piezoelectric energy harvester (UPEH) can obtain more energy at low speeds
An upright piezoelectric energy harvester (UPEH) composed of a piezoelectric cantilever with an upright cylinder attachment is investigated for converting wind kinetic energy into electricity

Summary

Introduction

With rapid development technologies, such as portable electronic devices, micro electro mechanical systems (MEMS) and wireless sensors, the reliance on the traditional battery has become a major obstacle due to expensive replacement, bulky volume, limited lifetime, and time-consuming maintenance. To evaluate the influence of the high-order vibration mode on energy harvester, Erturk [41] established the distributed nonlinear dynamic equation based on the massless piezoelectric beam. This kind of modeling method only considers the transverse displacement of the piezoelectric beam and has no regard for the influence of the axial force (pre-tension, vertical gravity) of the cantilever beam. To solve this problem, an energy approach is used to model and study the effects of the attached cylinder on the axial pressure of the cantilever beam.

Physics Statement and Mathematical Model

D3 dVp

E I2 φi2

Experimental Validation

Conclusions