低速时变气流激励下的宽带高效压电俘能方法及发电特性研究

The low-speed and time-varying airflow exists widely in nature and contains enormous energy. However, due to the low-speed and time-vary, the fluid kinetic energy is difficult to be harvested. Therefore, the efficient broadband piezoelectric energy harvesting method for low-speed and time-varying airflow is investigated in this project. Efficient broadband piezoelectric energy harvesters are proposed by taking flow-induced vibration, multi-modal energy harvesting, nonlinear magnetic energy harvesting, array energy harvesting of multi-piezoelectric vibrator into account. Coupled mathematics models with fluid-structure-electricity interaction will be established. The vibration response and energy harvesting performance induced low-speed and time-varying airflow 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 vibration and energy harvesting performance will be simulated and analyzed under the coupling of airflow with single/multi-piezoelectric harvesters. The energy transformation mechanism of fluid energy to electric energy will be revealed. Efficient broadband piezoelectric energy harvesting method for low-speed and time-varying airflow is proposed finally, which will provide new method and technical support for exploitation of new energy resources and provide a new continuous power supply method for the low-energy products and systems.

自然界分布广泛的低速时变气流环境蕴含着巨大的能量，却因流速低且不稳定而难以有效的俘获利用。本项目面向低速时变气流环境，开展宽带高效的压电俘能方法研究。通过考虑流致振动形式、多模态俘能、非线性磁力俘能和多压电振子阵列俘能等方面，规划宽带高效的压电俘能器构型；建立压电俘能器的流-固-电耦合数学模型，分析低速时变气流激励下的振动响应和能量输出特性；建立流-固-电多物理场仿真系统，仿真分析低速时变气流与单一/多个压电俘能器耦合作用下的流场演变特征、俘能器的振动俘能特性；揭示流场能到电能的能量转换机制，最终提出适用于低速时变气流环境的宽带高效压电能量采集方式，为风能的开发利用提供方法和技术指导，为低能耗电子产品/系统提供一种持续有效的能量供给方式。

随着低能耗电子产品/系统的应用越来越广泛，以电池、电子作为其主要供能源存在的弊端越发明显，如何持续稳定供能是制约其发展的主要技术瓶颈。自然界分布广泛的低速时变气流环境蕴含着巨大的能量，却因流速低且不稳定而难以有效的俘获利用。鉴于此，本项目提出了低速时变气流激励下的宽带高效压电俘能方法及发电特性研究，综述研究了压电俘能器流体能量俘获技术研究现状，提出了流致振动压电俘能的主要研究方向；面向低速时变流场环境激励，考虑流致振动形式，引入大应变、非线性磁力，开展了单一压电俘能器的低频宽频高效的压电俘能方法研究，提出了复摆式、倒立摆式、非对称弯扭复合式和非线性磁力单稳态涡激振动压电俘能方法，研究了涡激振动压电俘能器的交流和直流接口电路，建立了低速时变流场中压电俘能器流致振动俘能的流-固-电多物理场耦合数学模型，研究了压电俘能器的流致振动特性和发电能力，揭示了流-固-电多物理场耦合机制；引入多模态，提出了低速时变流体激励多个压电俘能器的耦合阵列俘能方法，规划了多个不同参数的俘能器阵列协同发电，运用流-固-电多物理场耦合仿真方法，研究了并行和串行双压电俘能器在流体激励下的流场演变特征、俘能器的振动俘能特性，揭示流场能/电能的能量转换机制。本项目提出了适用于低速时变气流环境的宽带高效压电能量采集方式，提高了压电俘能器在流致低频激励下的发电能力，实现了流-固-电的多物理场耦合，为多物理场耦合俘能提供一定的理论和技术支撑，为低能耗电子系统（网络）提供一种可持续、绿色环保的供能方式，研究成果可广泛应用于医疗、武器装备、无线网络传输、石油管运探测、海啸预警等领域，具有重要的研究价值和广阔的应用前景。