脉动流致振动宽频双稳态俘能技术

Broadband bistable energy harvesting induced by oscillating flow

本文设计一个水下流致振动双稳态俘能器,研究系统在不同波浪激励下的采集性能。首先,基于法拉第电磁感应定律,建立俘能器系统的机电耦合控制方程。利用谐波平衡法,推导波速远大于速度的小幅振动下的近似响应解析解,讨论了系统参数对输出电量的影响规律。通过和线性采集系统幅频曲线的对比,发现该俘能器具有宽频的优越采集性能。其次,计算系统在波速与速度不确定下的动力学响应,得到系统在不同频率下,具有周期、倍周期和混沌的复杂运动形式。最后,基于均方根方法,计算采集器系统在大幅激励时的统计特性。

In this paper,a bistable energy harvester for flow-induced vibration is designed,and the harvesting performance of the system under different wave excitations are studied.Firstly,the electromechanical coupling control equation of the harvester is established based on Faraday's law.By using harmonic balance method,the analytical solution of approximate response of the system under small excitation is analyzed,and the influence law of system parameters on output electric quantity is discussed.Compared with the amplitude-frequency curve of linear system,it is found that the harvester has superior performance of broadband acquisition.Secondly,the dynamic response of the system under large wave excitation is calculated,and the complex motion of the system with period,period doubling and chaos are obtained at different frequencies.Lastly,based on the root mean square method,the statistical characteristics of the system under large excitation are calculated.