Energy harvesting estimation from vibration of chopped fiber rod-reinforced microbeams with piezoelectric patch based on five parameter-surface-strain gradient Beam Model

Abstract

During the last years, the design and production of self-powered engineering structures gained extensive attention due to the shortage of nonrenewable energy resources and the increase in fossil fuel prices. To this end, the current numerical study focused on assessing the forced vibration behavior and energy harvesting capability of a silicon microbeam reinforced with chopped fiber rods (CFRs). This topic is important because it offers a novel approach to generate sustainable energy from ambient vibrations, addressing the growing demand for renewable energy sources while advancing structural health monitoring and smart materials technology. The piezoelectric patch is located at the top surface of the microbeam and is under the distributed harmonic force. The related governed relations are derived using the new theory of the five-parameter beam model, which also accounted for the Poisson effect, and solved by adopting the Galerkin method. The microscale effects are taken into account by employing strain gradient theory. Moreover, the effects of the top and bottom surfaces have accounted for the microbeam using Gurtin and Murdoch's theory. The outcomes of this research indicated that utilizing narrow-short length piezoelectric patches for Silicon microbeams yields the highest available output voltage. Compared to the homogeneous porosity distribution case, as the porosity coefficient reduced in the bottom and top surfaces of the microbeam, the voltage initial rise point decreased by about 13%. By increasing the porosity coefficient to 0.9, both voltage and displacement initial rise points are increased respectively by approximately 32% and 890%. As the piezoelectric patch thickness is decreased from 8 mu m to 6 mu m while the strain gradient theory is utilized, voltage and displacement initial rise points are increased respectively about 1066.67% and 1200%. Also, a simultaneous increase in CFRs vol. fraction from 5% to 10% and Silicon microbeam thickness from 7 mu m to 8 mu m caused about 37% improvement in dynamic deflections.