We carried out high-fidelity large-eddy simulations to investigate the effects of uniform blowing and uniform suction on the aerodynamic efficiency of a NACA4412 airfoil at the moderate Reynolds number based on chord length and incoming velocity of $$Re_c=200{,}000$$ R e c = 200 , 000 . We found that uniform blowing applied at the suction side reduces the aerodynamics efficiency, while uniform suction increases it. This result is due to the combined impact of blowing and suction on skin friction, pressure drag and lift. When applied to the pressure side, uniform blowing improves aerodynamic efficiency. The Reynolds-number dependence of the relative contributions of pressure and friction to the total drag for the reference case is analysed via Reynolds-averaged Navier–Stokes simulations up to $$Re_c=10{,}000{,}000$$ R e c = 10 , 000 , 000 . The results suggest that our conclusions on the control effect can tentatively be extended to a broader range of Reynolds numbers.

中文翻译：

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NACA4412 机翼上均匀吹吸的空气动力学效应

我们进行了高保真大涡模拟，以基于弦长和传入速度 $$Re_c=200{,}000 在中等雷诺数下研究均匀吹气和均匀吸力对 NACA4412 翼型的空气动力学效率的影响$$ R ec = 200 , 000 。我们发现在吸力侧施加均匀的吹风会降低空气动力学效率，而均匀的吸力会增加空气动力学效率。这一结果是由于吹气和吸力对皮肤摩擦、压力阻力和升力的综合影响。当应用于压力侧时，均匀的吹风提高了空气动力学效率。通过雷诺平均 Navier-Stokes 模拟分析压力和摩擦对参考案例总阻力的相对贡献的雷诺数依赖性，最高可达 $$Re_c=10{,}000{,}000$$R ec = 10 , 000 , 000 。