Performance of piezoelectric beam type energy harvester under flow-induced vibration

The objective of this research is to study the hydrodynamics and performance of piezoelectric PZT-5A patches in the context of turbulent fluid flow, with a specific focus on the impact of structural positioning on output performance. The numerical three-dimensional model consists of piezoelectric PZT-5A patches affixed to beams and positioned inside a uniform circular pipe. The modeling and simulation of the piezo-beams are conducted using ANSYS-Fluent software to analyze the vortex shedding phenomenon, which occurs due to induced vibrations from the interaction of the fluid with the PZT beams. A vorticity analysis is included to better understand the flow dynamics around the structures, revealing insights into the flow patterns that enhance energy harvesting. Additionally, a grid independence study is performed to ensure that the numerical results are reliable and not dependent on the grid resolution. This study confirmed that the results are consistent across different mesh densities, providing confidence in the accuracy of the simulations. The study also explores how turbulent flow increases the output voltage. It examines the effect of varying the spacing distance between two structures, considering three cases with distances of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>d</mml:mi> <mml:mn>2</mml:mn></mml:msub> <mml:mo>=</mml:mo> <mml:mn>0.0505</mml:mn></mml:mrow> </mml:math> m, 0.101 m, and 0.202 m, to evaluate their influence on natural frequencies and voltage output. The results indicate that the spacing significantly affects energy transfer and voltage generation, with the optimal configuration observed at <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>d</mml:mi> <mml:mn>2</mml:mn></mml:msub> <mml:mo>=</mml:mo> <mml:mn>0.202</mml:mn></mml:mrow> </mml:math> m. The maximum voltage value of 0.41264 V is observed from the structures across a broad frequency range. This voltage can be utilized in micro-scale applications such as cell phone charging, glowing LED lights, and bulbs, and can also be stored in batteries for future use.