论文标题
在跨气翼上拖动减少
Drag reduction on a transonic airfoil
论文作者
论文摘要
湍流皮肤摩擦阻力减少的流量控制应用于跨气翼，以提高其空气动力学性能。该研究基于直接数值模拟（具有多达1.8亿个单元）的可压缩湍流，围绕超临界机翼，在雷诺和马赫数为$ re_ \ re_ \ infty = 3 \ times 10^5 $和$ m_ \ infty = 0.7 $。通过跨度强迫控制在机翼的吸气侧的一小部分。除了局部减少摩擦外，控制还可以改变冲击波，并通过增加升力和减少阻力来显着提高机翼的空气动力学效率。因此，机翼可以在较低的攻击角度和较低的阻力下实现所需的升降机。飞机级别的估计表明可以大量节省。当控制权活跃时，由于小型应用程序区域，其能源成本就会忽略不计。我们建议，减少皮肤摩擦拖动不仅应视为一个目标，还应将其视为改善复杂流动流动性全球空气动力学的工具。
Flow control for turbulent skin-friction drag reduction is applied to a transonic airfoil to improve its aerodynamic performance. The study is based on direct numerical simulations (with up to 1.8 billions cells) of the compressible turbulent flow around a supercritical airfoil, at Reynolds and Mach numbers of $Re_\infty= 3 \times 10^5$ and $M_\infty =0.7$. Control via spanwise forcing is applied over a fraction of the suction side of the airfoil. Besides locally reducing friction, the control modifies the shock wave and significantly improves the aerodynamic efficiency of the airfoil by increasing lift and decreasing drag. Hence, the airfoil can achieve the required lift at a lower angle of attack and with a lower drag. Estimates at the aircraft level indicate that substantial savings are possible; when control is active, its energy cost becomes negligible thanks to the small application area. We suggest that skin-friction drag reduction should be considered not only as a goal, but also as a tool to improve the global aerodynamics of complex flows.
