水平轴风力机翼型动态失速的数值模拟

Numerical Simulation of Airfoil Dynamic Stall of Horizontal Axis Wind Turbine

采用数值模拟的方法对二维翼型NACA23012在非定常流动中的动态失速进行研究,分析翼型在振荡周期内升力系数随攻角的变化,并进一步研究俯仰运动的关键参数对翼型动态失速迟滞效应的影响,得出以下结论:振荡翼型的升力系数峰值大于静止翼型的升力系数峰值,使得风力机的实际输出功率大于理论计算值;平均攻角越大,临界失速攻角越大,升力系数峰值越大;振幅及衰减频率的增加均使得动态失速迟滞效应增强。模拟结果与试验结果吻合较好,用模拟的方法分析振荡翼型的气动特性参数的变化趋势是可行的。

Dynamic stall of the airfoil NACA23012 was studied by numerical simulation method.The coefficient of lift was calculated in different angle of flow attack in an oscillation cycle.Further more,the hysteresis effect induced by the key parameters of the pitching movement was analyzed.The results show that the peak lift coefficient of a pitching airfoil is larger than that of static airfoil and the actual output power of the wind turbine is larger than its theoretical value.The more the mean angle of attack is,the larger the lift coefficient and the critical stall angle of attack are.With the increases of the oscillation amplitude and the reduced frequency,the hysteresis effect becomes more significant.The simulation results are well with the experimental data,so it is feasible to analyze the trend of the aerodynamic parameters of the pitching airfoil using simulated values.