锯齿形格尼襟翼气动性能的实验研究

用低速风洞测力试验和襟翼处绕流的PIV测量试验研究锯齿形格尼襟翼在不同偏角下的增升效益.结果表明:锯齿形格尼襟翼能明显提高翼型的升力系数和大升力系数下的翼型升阻比,对于给定的襟翼弦长,存在一个最佳的襟翼偏角,在此偏角下,翼型升阻比不仅在大升力系数下有明显提高,而且在中小升力系数时升阻比也有一定的提高.PIV测量表明从锯齿形格尼襟翼的齿边向上卷起的流向涡使上翼面后部气流向翼型表面吸附,推迟了上翼面气流的分离.

Experimental Investigation on Aerodynamic Performance of Serrated Gurney Flap

Force and PIV local flow measurements were conducted in a low speed wind tunnel to study the effectiveness of serrated Gurney flap at different deflections. The results showed that the serrated Gurney flap could significantly increase the lift coefficients and the ratio of lift to drag of the airfoil with high lift coefficients. For a given serrated Gurney flap, there was an optimum deflection, At which, the lift drag ratio of the airfoil can increased not only at high lift coefficient but also at the low to middle angle of attack. It was also found that near stream wise vortices shed from the serrated edges can make the flow attach to the upper surface near the trailing edge and can delay flow separation.