The paper focuses on the application of the blowing/suction technique to control incompressible turbulent boundary layer on 2-D low-speed airfoils. Analysis of the experimental and numerical results obtained with the combined flow control technique through the high-technological perforated sections is carried out. This control method turns out to be a more effective way to improve aerodynamic performance of airfoil compared to isolated forcing. Such technology allows us in the studied conditions to provide an effect, characterized by an increase in the airfoil lift and, ultimately, an increment in lift-to-drag ratio Δ K/K max by about 0.06. For all combinations of the control forcing, the simplified mechanism responsible for changes in the airfoil aerodynamic performances is almost identical: the pressure increases due to blowing on one side of the airfoil and decreases due to suction on the opposite side, thus, leading to enhancement of the lift force and, as a consequence, to a gain in the lift-to-drag ratio. Also evaluation of the efficiency of the considered control technique with allowance for energy expenses is given.

中文翻译：

---

低速翼型的组合吹/吸流量控制

本文重点研究吹/吸技术在二维低速翼型不可压缩湍流边界层控制中的应用。对通过高科技穿孔段使用组合流量控制技术获得的实验和数值结果进行了分析。与孤立强迫相比，这种控制方法被证明是一种更有效的提高翼型气动性能的方法。这种技术使我们能够在所研究的条件下提供一种效果，其特征是翼型升力增加，最终升阻比 Δ K/K max 增加约 0.06。对于控制力的所有组合，负责翼型空气动力学性能变化的简化机制几乎相同：压力因机翼一侧的吹气而增加，因另一侧的吸力而减少，从而导致升力增强，从而导致升阻比增加。还对考虑的控制技术的效率进行了评估，并考虑了能源费用。