中文摘要：

采用大涡模拟法（LES）对自行开发设计的100W小型水平轴风力机在来流风速为8m／s、湍流强度为0．4％时的尾流进行数值模拟计算，计算中提取流场稳定后的x、y、z3个方向的瞬间速度、压力等参数的600个数据样本，计算得到尾流（1≤y/d≤20）内轴向速度和湍流强度的均方根值，分析风力机尾流内时间平均轴向速度、湍流强度及涡结构等的特征。结果表明：在y／d=5风轮下游位置，轴向速度亏损仍很严重，仅约为来流风速的50％。且在州≤5的范围内尾流宽度均略大于风轮直径，尾流膨胀现象不明显。一直到y／d〉17以后的位置，尾流效应才开始变得不明显；与来流的低湍流特性相比，尾流内的湍流强度大幅提高，在y／a=5位置，湍流强度达到最大，最大湍流强度值为来流湍流强度的30倍，且在近尾流区域存在的4个湍流峰值分别对应叶片的叶尖和叶根位置。

英文摘要：

100 W self-designed horizontal axis wind turbine in wake with free stream velocity of 8 m/s at the inlet and turbulence intensity （TI） of 0.4% was numerically simulated and calculated by large Eddy simulation （LES）. 600 data samples, such as instantaneous velocities and pressure in x, y and z direction after the flow field becoming stable were extracted in the calculation, the calculation obtained the root-mean-squares of axial velocity and the turbulence intensity （T I） in wake （l≤y/d≤20） and analyzed time-average axial velocity, turbulence intensity and vorticity structure etc. characteristics. The results showed that the axial velocity is still very serious loss at the y/d=5 wind turbines downstream position, only about 50% of the wind to flow. And the width of the wake is little larger than the wind wheel diameter when y/d≤5, the wake expansion is not obvious. When y/d〉 17, the wake influence starts becoming non-obvious. TI in wake of the wind turbine increases considerably. The maximum TI is observed at the y/d =5, which is 30 times as big as the free- stream TI at the inlet. In the TI curves, 4 turbulence peaks are observed in the near-wake in the region corresponding to positions of blade tip and root.