垂直轴风力发电机非定常流场分析及能量收集器位置优化

Unsteady Flow Field Analysis and Energy Harvester Position Optimization of Vertical Axis Wind Turbine

垂直轴风力发电机中能量分布梯度影响能量收集器的布置。为了探究风轮在转动过程中内部流场能量梯度的变化,采用剪切应力运输k-ω模型和滑移网格技术对风轮内部流场进行数值建模和仿真,在此基础上,引入能量梯度理论探索风轮内部动态流场的能量梯度分布状态,得到风轮内部能量梯度最大值是在方位角180°下风轮内部尾流和涡旋发生位置;对30°60°90°、120°、150°、180°方位角下叶片表面压力进行分析对比得知:叶片前缘区域在风轮旋转前后时刻对比压差变化率最大可达到66.7%,能量收集器布置在该区域可较好地收集耗散的能量。以上研究结果为能量收集技术在风电机上提高能量利用率方面的应用提供了参考。

The energy distribution gradient affects the arrangement of the energy harvester in the vertical axis wind motor.To explore the variation of the energy gradient in the internal flow field of the wind wheel of the vertical axis wind motor during rotation,the shear stress transfer(SST)k-ω model and the sliding mesh technology are used in the modeling and simulation of the internal flow field of the wind wheel under certain conditions.Then,the energy gradient theory is introduced to explore the energy gradient distribution of the dynamic flow field inside the wind wheel.It is obtained that the maximum value of the energy gradient K inside the wind wheel is the wake and vortex occurrence position inside the wind wheel at the azimuth angle of 180°.The analysis and comparison of the blade surface pressure at the azimuth angles of 30°,60°,90°,120°,150°,and 180°show that the maximum change rate of the contrast pressure difference before and after the rotation of the wind wheel at the blade leading edge region can reach 66.7%,and energy harvesters arranged in this region can collect the dissipated energy more efficiently.The research results can provide a reference for the application of energy collection technology for improving the energy utilization rate of wind turbines.