密度比对半主动拍动翼海流能采集系统影响研究

Mass ratio effect on ocean current energy harvesting efficiency through a semi-active flapping foil

针对基于振荡水翼的海流能采集系统水动力学机理尚不完全清楚的问题,对半主动海流能采集系统的各项参数进行了数值模拟研究。半主动海流能采集系统俯仰运动由执行机构通过外力控制,升沉运动由作用在水翼上的水动力激发。先研究了最大有效攻角、拍动频率对系统能量采集效率的影响,进一步研究了水翼与流体的密度比对系统能量采集效率的影响。研究结果表明,密度比对系统的能量采集效率有较大影响,在所选用的参数范围内,能量采集效率随着密度比减小而增大。因此,水翼本身的惯性的影响在半主动海流能采集系统的研究中不可忽略。

Aiming at performance of energy harvesting efficiency through a semi-active flapping foil, a computational fluid dynamic method was carried out. To achieve such an energy harvesting system, mode coupling between multiple degrees of freedom was usually needed, which means controlling one motion mode while extracting energy via the other following modes.First, the maximum effective angle of attack and flapping frequency were examined. Then, with more interests, the mass ratio between the wing and its surrounding fluid was investigated. The results indicate that the mass ratio significantly affects the energy extracting efficiency. During the parameters concerned, the efficiency increases along with the decrease of the mass ratio. This suggests that the mass ratio, or inertial effects has to be taken into account when evaluating the performance of the flapping foil based energy harvesting system.