翼型表面随行波结构流动控制的数值研究

针对翼型表面的流动分离,采用数值模拟方法研究随行波结构流动控制的机制。为了验证计算方法的可靠性,将翼型表面静压曲线与实验测试结果进行对比,发现两者吻合程度较好。数值计算结果表明,适当增加随行波的相对弦长长度,有助于改善翼型的气动性能。当攻角小于3°时,随行波位于分离点之前,沟槽内形成顺时针旋转的二次涡,有助于加速边界层低速条带;在大攻角下,随行波位于分离点之后,顺时针卷起的分离涡在沟槽内形成逆时针旋转的二次涡,与分离涡互为反向涡对,减小了尾缘分离区范围。翼型表面随行波能有效地控制边界层流动。

Numerical study on flow control of traveling wave structure on the airfoil surface

The mechanism of flow separation controlled by the traveling wave structure on the airfoil surface was studied using numerical simulation method. In order to verify the reliability of the calculation method, the static pressure on the airfoil surface was compared with the experimental results. Good agreement was observed. In addition, it was found from the numerical results that increasing the relative wavelength of traveling wave appropriately could improve the aerodynamic performance of the airfoil. When the angle of attack was less than 3°, the traveling wave was located before the separation point, and the secondary vortex with a clockwise rotation was formed in the groove, which could accelerate the low-speed strip in the boundary layer. At larger angle of attack, the traveling wave was located behind the separation point. The rolled separation vortex led to the formation of secondary vortex with a counter-clockwise rotation in the groove, which was a reverse vortex pair with the separation vortex and could reduce the separation zone of trailing edge. The traveling wave on the airfoil surface could effectively control the flow in the boundary layer.