风力机动态偏航时对风轮气动性能影响的数值模拟研究

Numerical Simulation of the Influence of Dynamic Yaw on the Aerodynamic Performance of Wind Turbine

本文是对动态偏航风力机输出功率和风轮表面的压力分布进行了研究。以某S翼型风力机叶片为研究对象,采用有限元方法,模拟叶片在额定工况下以10°/s的旋转速度从正对来流风开始顺时针匀速偏转30°。在动态偏航过程中取10°,20°两个偏航角位置时的风轮表面气动力及5°,10°,15°,20°,25°,30°六个偏航角下风轮的输出功率分别进行气动力及输出功率对比,结果发现:同一偏航角下,风力机动态偏航时,三支叶片间存在不平衡气动力;同一偏航角同一叶片相同径向位置,风轮动态偏航时压力面与吸力面的压强差小于风轮静态偏航时压力面与吸力面的压强差。风力机发生动态偏航时,风力机受气动力变化幅度较大,输出功率会较大波动。

At present, only the aerodynamic performance of fixed yaw wind turbine has been studied. This paper studies the output power of dynamic yaw wind turbine and the pressure distribution on the surface of wind turbine.The finite element method was adopted to simulate the blade rotates at a rotating speed of 10°/s for an S airfoil wind turbine, starting from the positive incoming wind, with a constant clockwise deflection of 30° under the rated condition. In the process of dynamic yaw, the comparison of the aerodynamic force on the rotor surface between 10°and 20°yaw angle position is analyzed and the output power of wind turbine rotor under the 5°,10°,15°, 20°,25°,30°six drift angle are compared. The analysis result found that under the same yaw angle in during wind turbine dynamic yaw, the imbalance aerodynamic force between the three blade, under the same yaw angle and the same radial position of the same blade, the pressure difference between the pressure surface and the suction surface is less than the pressure difference when the wind rotor in yaw dynamically. When the wind turbine has a dynamic yaw, the wind turbine is subjected to a large range of aerodynamic changes, and the output power will fluctuate greatly.