考虑鲁棒性的超临界翼型激波控制鼓包减阻研究

本文主要采用CFD方法研究超临界翼型的激波控制鼓包减阻技术,分析了鼓包形状参数对减阻效果和鲁棒性的影响规律.计算结果显示,鼓包的减阻效果受位置影响较大,当鼓包最高点与干净翼型的激波位置相同时减阻效果较好,鼓包高度过高对减阻效果不利,而较长的鼓包可在更大的高度范围内实现减阻.鼓包还可以通过弱化激波,抑制附面层分离,延缓超临界翼型抖振现象的发生.计算结果显示,鼓包减阻技术整体而言工作范围较窄.但经过设计,较长且较低的鼓包可以在较大的升力范围内具有减阻效果,并且减阻效果对形状变化及雷诺数变化不敏感,还能有效提高阻力发散马赫数,鲁棒性要明显优于较短较高的鼓包,具有工程应用的潜力.

The drag reduction study of the supercritical airfoil with shock control bump considering the robustness

The shock control bump of supercritical airfoil is numerically investigated by Computational Fluid Dynamics in present paper. The influence of the geometry parameters of the bump is studied by considering the drag reduction performance and robustness. The results show that, the bump location strongly affects on the drag reduction. The best performance is obtained when locating the bump crest at the shock position of the clean airfoil. Higher bump is worse for the drag reduction, while longer bump has good effect in a bigger height range. The bump can effectively weaken the shock wave, suppress the boundary layer separation, and extend the buffet onset boundary, but its working lift coefficient range is relatively narrow. The robustness is an important requirement of engineering application. The results of robustness analysis shows that, the longer and lower bump is more engineering acceptable than the shorter and higher bump, while it could not only improve lift-drag ratio in larger lift coefficient range insensitive to the changes of shapes and Reynolds number, but also increase the drag divergence Mach number.