面向低速水流的复合流激振动压电俘能机理与方法研究

In nature, both vortex-induced vibration (VIV) and wake-induced vibration (WIV) of flow-induced vibration are common phenomena in low-speed water flow, such as rivers, ocean currents and tidal streams, etc. The above flow-induced vibration contains the infinite energy. However, due to the low-speed, the kinetic energy of water flow is difficult to be harvested. Therefore, in this proposal, the flow-induced vibration is regarded as the exciting source. The configuration planning of the piezoelectric energy harvesters will be performed by taking the shape, number, structure, vibration modal, and coupling mode of oscillators into account. Coupled mathematics models with fluid-structure-electricity interaction will be established for the above harvesters with different configurations. The dynamic response of the fluid-induced vibration and energy and the energy output characteristics of the piezoelectric energy harvesters will be analyzed. The fluid-structure-electricity coupling simulation system with multi-physics fields will be established. The evolution characteristics of the flow field, the strain law of structures, and the energy transformation mechanism in the flow-induced composite vibration will be simulated and analyzed. The piezoelectric harvesting mechanism with low-frequency, broadband, and high efficiency revealed. This project will provide new methods and technical supports for the continuous power supply of the low power consumption system and the development and utilization of new energy. This project has broad prospects in application and social benefits.

自然界中的河流、海洋流和潮汐流等低速水流环境广泛存在着涡激振动和尾流激振两种流激振动形式，蕴含着无穷的能量。然而因流速低，其动能不易被俘获。本项目将水的流激振动作为激励源，考虑俘能器振子的形状、数量、结构形式、振动模态以及耦合方式等的不同对压电俘能器进行构型规划研究。建立各种构型压电俘能器在流激振动场中的流-固-电耦合的数学模型；分析其流激振动响应和能量输出特点；建立流-固-电多物理场耦合仿真系统；仿真分析复合流激振动压电俘能过程中流场的演变特征、结构的应变规律、能量的转换机制；揭示其低频、宽带、高效的压电俘能机理。该项目将为低能耗微电子系统的持续供能与新能源的开发利用提供新的方法和技术，具有较大的应用前景和社会效应。

自然界中的河流、海洋流和潮汐流等低速水流环境广泛存在着涡激振动和尾流激振两种流激振动形式，蕴含着无穷的能量。然而因流速低，其动能不易被俘获。本项目将水的流激振动作为激励源，考虑俘能器振子的形状、数量、结构形式、振动模态以及耦合方式等的不同对压电俘能器进行了构型规划研究。主要研究有以单一圆柱的涡激振动为激励源，设计了流激复摆振动式单振子压电俘能器，通过仿真和实验的方法研究了复摆式压电俘能器在低速水流环境中的涡激振动响应和俘能特性；同时研究了偏心圆柱引发的弯振扭振结合的俘能器，建立了工作在弯曲和扭转振动复合的情况下俘能器流-固-电多物理场耦合的非线性数学模型；设计了一款悬臂梁压电-电磁复合水下俘能器，考虑线圈电感和磁场空间分布，建立了耦合俘能器的分布参数近似模型；研究了一种可完全浸没水中的悬臂梁式俘能器，建立了单个俘能器的流-固-电耦合数学模型并分析了各个参数的影响规律；探索了两个俘能器串行水下排布时的互相影响规律，建立了双俘能器的流-固-电耦合Fluent仿真模型，模拟了双俘能器的输出特性和规律，实验研究了两个俘能器开路输出电压随中心距变化的规律；在本项目研究过程中，产生了一些新的研究想法。提出了一种自供电的径向压电振膜新型传感器，对其灵敏度和震荡流速进行了研究，为水下航行器提高能效提供了良好的前景感知和操纵能力。本项目发表SCI论文18篇，EI及会议论文6篇；培养博士生1名、硕士生4名；申请发明专利5项，其中已经获得授权3项；项目的研究结果为低能耗微电子系统的持续供能与新能源的开发利用提供了新的方法和技术，具有较大的应用前景和社会效应。