边界层和压力滞后对翼型动态失速性能的影响

INFLUENCE OF BOUNDARY LAYER AND PRESSURE LAG ON DYNAMIC STALL PERFORMANCE OF AIRFOIL

为优化动态失速模型经验常数,提升动态失速发生时翼型气动性能预测精度,该文基于B-L动态失速模型,结合内蒙古工业大学风能太阳能利用技术教育部重点实验室风洞实验数据,探究压力滞后及边界层滞后时间常数对翼型动态失速性能的影响。主要结论如下:压力滞后与边界层滞后时间常数对动态升力系数的影响较大且与平均攻角有关。当平均攻角相对较小且气流处于附着流动与分离流动之间时,适当减小时间常数可使动态失速模型计算结果更接近实验值;当平均攻角相对较大,气流处于分离流动与完全分离流动时,可适当增大时间常数值。压力滞后与边界层滞后时间常数对动态阻力系数的影响不显著。动态升力系数仅在攻角逐渐减小的完全分离流动过程中,随着边界层滞后时间常数的增大而减小。

To optimize the empirical constants in dynamic stall model and improve the prediction accuracy of airfoil aerodynamic performance when dynamic stall occurs,the influence of pressure lag and boundary layer lag time constant on the dynamic stall performance is explored,using the B-L dynamic stall model and the wind tunnel experiment in the Key Laboratory of Wind and Solar Energy Utilization Technology of the Ministry of Education at Inner Mongolia University of Technology.The main conclusions are as follows.The time constants of pressure lag and boundary layer lag have great influence on the dynamic lift coefficient,which is related to the average angle of attack.When the average angle of attack is relatively small and the flow is between the attached flow and the separated flow,appropriately reducing the time constant can make the calculated results of the dynamic stall model closer to the experimental values.When the average angle of attack is relatively large and the flow is in separated flow or completely separated flow,the time constant value can be appropriately increased.The influence of pressure lag and boundary layer lag time constant on the dynamic drag coefficient is not significant.The dynamic lift coefficient only decreases with the increase of boundary layer lag time constant in the completely separated flow process where the angle of attack decreases gradually.