Analysis of Two-degree-of-freedom Beam for Rotational Piezoelectric Energy Harvesting

Core Concepts

Design and analyze a rotational energy harvester with geometric nonlinearity for enhanced efficiency.

Abstract

This study explores a two-degree-of-freedom piezoelectric energy harvester designed for rotational motion. The model considers geometric nonlinearity due to longitudinal displacement, leading to precise simulation results. By increasing rotating speed, the first resonant frequency rises while the second decreases. The study investigates expanding bandwidth using nonlinear external forces like mechanical stoppers and magnetic force. Results show potential bandwidth broadening at resonance frequencies by 1.17 Hz and 0.33 Hz, respectively. Previous research on cantilevered beam energy harvesters under base excitations is compared to rotational excitation challenges, emphasizing lateral deflection effects. Linear energy harvesters' limitations in harvesting bandwidth are addressed through methods like mechanical structure optimization, external circuitry, and nonlinear techniques. Nonlinear methods optimize rotational energy harvesting through inherent system characteristics or externally introduced forces like impact or magnetic forces. Magnetic force applications in rotational systems are explored for improved efficiency and power output. Multi-modal technology is studied for wideband energy harvesting, focusing on low-frequency environments with tri-modal vibration capabilities. Hybrid systems methods combine different configurations for better output performance in rotational energy harvesting applications. The study introduces a two-degree-of-freedom rotational energy harvester design with potential bandwidth enhancement using impulse and magnetic forces.

Stats

The proposed harvester can broaden the bandwidth by 1.17 Hz and 0.33 Hz at the first and second resonance frequencies. Mode veering is observed at about 15 Hz in the relationship between driving frequency and natural frequency of the PEH.

Quotes

Key Insights Distilled From

Analysis of a Two-degree-of-freedom Beam for Rotational Piezoelectric Energy Harvesting

by Xiang-Yu Li,... at arxiv.org 03-18-2024

https://arxiv.org/pdf/2403.10269.pdf

Deeper Inquiries

How can the introduction of impulse forces impact the efficiency of rotational energy harvesting

The introduction of impulse forces can have a significant impact on the efficiency of rotational energy harvesting systems. When a stopper is used to limit the displacement of the beam, it can lead to controlled collisions that result in additional mechanical energy being transferred to the piezoelectric layer. This sudden force applied during collision can generate higher voltage outputs due to the rapid change in momentum and deformation. By harnessing this impulse force effectively, the overall energy conversion efficiency of the system can be improved as more mechanical energy is converted into electrical energy.

What are the implications of mode veering on the performance of piezoelectric energy harvesters

Mode veering in piezoelectric energy harvesters (PEHs) has implications for their performance and operation. Mode veering occurs when two modes cross each other as a function of frequency, leading to changes in mode shapes and natural frequencies. In PEHs, mode veering affects how different vibration modes interact with external excitations or disturbances. It influences resonance behavior, bandwidth utilization, and overall power generation capabilities. In terms of performance implications: Resonance Behavior: Mode veering can cause shifts in resonant frequencies which may impact how efficiently the PEH responds to external stimuli. Bandwidth Utilization: Changes in mode shapes near mode veering points can affect the bandwidth over which efficient energy harvesting occurs. Power Generation: The interaction between different modes during mode veering could influence power output levels at specific frequencies. Understanding and managing mode veering is crucial for optimizing PEH designs for maximum efficiency across varying operating conditions.

How can hybrid systems methods be further optimized for enhanced output in rotational energy harvesting applications

Hybrid systems methods offer promising avenues for enhancing output in rotational energy harvesting applications through meticulous design strategies that combine multiple mechanisms. To further optimize these hybrid systems methods: Integration Optimization: Enhance integration between different components within hybrid systems by fine-tuning interfaces and interactions between electrostatic or electromagnetic elements. Material Selection: Optimize material properties based on specific requirements such as flexibility, durability, conductivity, etc., ensuring compatibility with various components within hybrid setups. Control Strategies: Implement advanced control algorithms that dynamically adjust system parameters based on real-time feedback data from sensors embedded within hybrid systems. Efficiency Analysis: Conduct detailed efficiency analyses using computational tools like finite element analysis (FEA) or multiphysics simulations to identify areas where improvements are needed. By focusing on these optimization strategies along with continuous research advancements, hybrid systems methods can achieve even higher levels of performance and output in rotational energy harvesting applications.