论文标题
液滴发电机能源效率的流体动力限制
Hydrodynamic constraints on the energy efficiency of droplet electricity generators
论文作者
论文摘要
在过去的一年中，液滴下降的电能发电效率增加了一百倍。但是，即使是这些最新设备，也只能提取一小部分液滴能量。在本文中，我们从理论上研究了流体动力和电损失在限制液滴发电机效率（DEG）方面的贡献。指出电力能量转换发生在立即落后液滴冲击的后坐力中，我们确定了对现有液滴发电机的三个限制：（i）撞击速度受到限制以保持液滴完整性； （ii）大部分液滴机械能在用底物克服粘性剪切力中浪费； （iii）底物的电荷不足。在所有这些效果中，我们发现，在扩散过程中，粘性耗散损失了多达83％的总能量。通过使用级联的DEG设备来降低液滴动能，可以最大程度地减少这种损失，这可能会使未来的设备效率提高到10％以上。
Electric energy generation from falling droplets has seen a hundred-fold rise in efficiency over the past year. However, even these newest devices can only extract a small portion of the droplet energy. In this paper, we theoretically investigate the contributions of hydrodynamic and electric losses in limiting the efficiency of droplet electricity generators (DEG). Noting that the electro-mechanical energy conversion occurs during the recoil that immediately follows droplet impact, we identify three limits on existing droplet electric generators: (i) the impingement velocity is limited in order to maintain the droplet integrity; (ii) much of droplet mechanical energy is squandered in overcoming viscous shear force with the substrate; (iii) insufficient electrical charge of the substrate. Of all these effects, we found that up to 83% of the total energy available was lost by viscous dissipation during spreading. Minimizing this loss by using cascaded DEG devices to reduce the droplet kinetic energy may increase future devices efficiency beyond 10%.
