错列风力机尾流的实验研究

Experimental research of wakes behind staggered wind turbines

为了更好地研究水平轴风力机的尾流结构及其对下游风力机出力性能的影响,将两台风力机错列布置,使用压差式精密风速仪和手持风速仪对风力机的尾流场进行了测量.通过比较单风力机和两台错列布置风力机的速度、压力和诱导速度,分析了风力机之间的尾流干扰问题.结果表明,上游风力机的尾流会使下游风力机的来流风速小于设计风速.两台风力机尾流重叠区的湍流度增加,尾流干扰增强,随着测量间距的增大,轴向速度先减小后增大.下游风力机5倍风轮直径处,尾流场速度基本恢复到主流速度.

In order to study in a better way the wake structure of horizontal axis wind turbine and its impact on output performance of downstream wind turbine,two wind turbines are staggeringly arranged and precise differential anemometers and hand-held anemometers are employed to measure the flow field of the wake.By means of comparing the wind speed,pressure,and induced speed in the wake behind of single wind turbine with that of two staggeringly arranged wind turbines,the problem of wind turbine wake interference is analyzed.The result shows that the wake of the upstream wind turbine will make the oncoming wind speed in front of downstream wind turbine less than design wind speed.In overlapping area of two wakes behind the wind turbine,the turbulence will increase and wake interference increase,thereby.With the increasing of measurement spacing,the axial wind speed will decrease at first and then increase.Beyond the distance of five times of turbine rotor diameter,the wake speed will basically recover to be mainstream speed.