液滴发电机的新充电模式及影响因素  

New charging mode of a droplet generator and its influencing factors

作　　者：夏雨晨 周致富[1] 宋德培 黄羿珲 高雨轩 陈斌[1] Yuchen Xia;Zhifu Zhou;Depei Song;Yihui Huang;Yuxuan Gao;Bin Chen(State Key Laboratory of Multiphase Flow in Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]西安交通大学,动力工程多相流国家重点实验室,西安710049

出　　处：《科学通报》2021年第34期4477-4484,共8页Chinese Science Bulletin

基　　金：国家自然科学基金(52176163);国家重点研发计划政府间国际科技创新合作重点专项(2017YFE0134200);航空基金民发专项(2019ZB070002)资助。

摘　　要：基于液滴撞击摩擦起电效应的液滴发电机(droplet-based electricity generator, DEG)可以将雨水等液滴的机械能转换成电能.近年来,其因具有广泛的应用前景而受到密切关注.但是,目前DEG仍存在带电荷能力与输出电压上限较低等问题.本文发现了一种适用于DEG的新充电模式,即在通过液滴撞击聚四氟乙烯(polytetrafluoroethylene, PTFE)薄膜进行充电的基础上,对PTFE薄膜表面附加往复摩擦,以对其进行预充电.相比单纯的液滴撞击充电,新充电模式可以使DEG的输出电压提高约2.3倍,进而可以匹配高压用电环境.本文研究了摩擦工具、液滴下落频率与高度以及停止工作时长这4种因素对DEG发电效果的影响规律.研究结果可为提高DEG发电效果提供新思路与新方法.The traditional fossil energy is becoming increasingly scarce and is a main cause of environmental pollution. Therefore,power generation by fossil fuels will face great challenges in future. Hydraulic power generation has the advantages of being relatively clean, renewable and widely available. However, this way mainly uses electromagnetic generators that are heavy, bulky, and become inefficient with low water supply. In addition, it is not suitable for harvesting energy from water in the form of raindrops which store huge clean energy. The droplet-based electricity generator(DEG) can convert the mechanical energy of droplets such as rain water into electrical energy. DEG has attracted increasing attention in recent years due to its wide application prospects in outdoor lighting, portable mobile electronic devices and automobile glass power generation. However, the DEG still has some critical problems, such as the upper limit of charge capacity and the upper limit of output voltage, which limit its application in practice. In this study, a DEG experimental system is developed firstly, which consists of a droplet generator, electricity generating structures, supporting structures and voltage measurement equipment. The electricity generating structure is the most important part of the whole system, which comprises a polytetrafluoroethylene(PTFE) film on an indium tin oxide substrate(ITO) plus an aluminium electrode. The PTFE, a promising electret material with high charge storage capability and stability could serve as an ideal reservoir for charge storage, while electrostatically inducing opposite charge of the same amount on the ITO for possible charge transfer to an aluminium electrode. A falling water droplet spreads on the PTFE surface, which bridges the originally disconnected components(the PTFE/ITO and aluminium electrode) into a closed-loop electrical system. Then, a new charging mode for DEG has been discovered through extensive experiments. That is, a reciprocating friction experimental machine is used t

关 键 词：摩擦起电 液滴发电机 聚四氟乙烯薄膜 新充电模式 

分 类 号：TM31[电气工程—电机]