【摘要】 【目的】风力机尾流影响风电场的整体功率输出，对尾流特性进行分析是研究偏航控制对尾流影响的关键。为此，研究了上游风力机不同偏航角对尾流特征(如湍流积分尺度、功率谱密度等)以及尾流中涡流运动等方面的影响，以深入了解偏航状态下风力机尾流特性。【方法】采用风洞对0°、15°、30°偏航角的风力机下游尾迹演化规律进行研究。使用湍流积分尺度及功率谱密度等描述尾流特征，并以此分析不同特征点之间的相关性。【结果】偏航角对水平方向的尾流影响较小，湍流积分尺度变化不大；垂直方向上的湍流积分尺度在不同偏航角下具有较大的波动。通过对功率谱密度的分析，进一步量化了涡流运动对尾流湍动能的贡献。0°偏航时的来流受风力机旋转的扰动程度比15°偏航时小；但偏航角的增大并不总是导致风轮对来流的破坏程度增加，30°偏航时对来流涡结构的解耦作用比15°偏航时小。【结论】偏航角对风力机尾流在水平和垂直方向上的影响具有明显差异；功率谱密度分析为理解涡流运动对尾流湍动能的贡献提供了量化依据，有助于深入研究尾流中的能量传递和流动机制；偏航角与风轮对来流的扰动和解耦作用之间并非简单的正相关关系，这为风力机的优化运行和风电场的布局提供了参考依据。更多还原

【Abstract】 [Objectives] The wake of wind turbine affects the overall power output of wind farm.The analysis of wake characteristics is the key to study the influence of yaw control on wake.Therefore,the effects of different yaw angles of the upstream wind turbine on the wake characteristics(such as turbulence integral scale,power spectral density,etc.) and the eddy current motion in the wake were studied,to understand the wake characteristics of the wind turbine under yaw conditions.[Methods] The wind tunnel was used to study the evolution law of the downstream wake of the wind turbine at 0°,15° and 30° yaw angles.The turbulence integral scale and power spectral density were used to describe the wake characteristics,and the correlation between different feature points was analyzed.[Results] The yaw angle has little effect on the horizontal wake,and the turbulence integral scale does not change much.The turbulent integral scale in the vertical direction has large fluctuations at different yaw angles.Through the analysis of the power spectral density,the contribution of eddy current motion to the turbulent kinetic energy of the wake is further quantified.The incoming current at 0° yaw is less disturbed by the rotation of the wind turbine than that at 15°.However,the increase of yaw angle does not always lead to an increase in the damage degree of wind turbines to the incoming current,and the decoupling effect on the incoming vortex structure at 30° is smaller than that at 15°.[Conclusions] There is a significant difference in the influence of yaw angle on the horizontal and vertical directions of wind turbine wake.The power spectral density analysis provides a quantitative basis for understanding the contribution of eddy current motion to the turbulent kinetic energy of the wake,which is helpful for in-depth study of the energy transfer and flow mechanism in the wake.There is not a simple positive correlation between the yaw angle and the disturbance and decoupling of the wind turbine on the incoming stream,which provides a reference for the optimal operation of the wind turbine and the layout of the wind farm.更多还原