低雷诺数下吹吸气射流对NACA0012翼型气动性能的影响

基于Favre过滤的大涡模拟方法,对雷诺数Re=10^4,迎角α=6°下的NACA0012翼型上表面吹吸气射流进行了数值模拟,从翼型周围流场流线图、速度场云图、上下表面压力系数曲线以及上表面边界层位移厚度等多角度地分析了射流位置以及速度变化对翼型气动性能的影响。结果表明:射流位置对翼型气动性能影响较大,且吸气射流要明显优于吹气射流。对于吸气射流,前缘吸气要明显优于中后缘吸气,可有效增升减阻,并减小翼型尾部流动分离,抑制翼型气动参数扰动,其最佳吸气位置随着速度的增大逐渐向下游移动;而吹气射流对翼型气动系数的作用效果较差,但中后缘的吹气射流可减小飞行过程中的气动扰动量,且吹气越大,效果越明显。

The effect of blowing/suction jet on the aerodynamic performance of airfoil NACA0012 at low Reynolds number

Based on large eddy simulation obtained from Favre filtering,the numerical simulations for the blow/suction jet on the upper surface of airfoil NACA0012 have been conducted at Reynolds number Re=10^4 and angle of attackα=6°.The effects of jet location and velocity on airfoil aerodynamic performance have been discussed from the variations of streamlines pattern,velocity contour,upper and lower surface pressure coefficients,and displacement thickness of upper surface boundary layer.The results show that,the jet location has a great influence on the aerodynamic performance of the airfoil and the control effects of suction jet is obviously better than that of blowing jet.For the suction jet,the front edge suction can effectively increase the lift and reduce the drag,and it can also suppress flow separation of airfoil,and restrain the disturbance of aerodynamic parameters of airfoil during flight.The optimum suction location gradually moves downstream with the increase of suction velocity.Relatively,the control effect of blowing jet on aerodynamic coefficient of airfoil is not good enough.However,the blowing jet at the middle and rear edge can reduce the aerodynamic disturbances,and the larger the blowing velocity,the more obvious its effect.