In this study, a dynamic stall control strategy, called the co-flow jet (CFJ), is applied to the rotor airfoil. The effect of the CFJ on the unsteady dynamic stall characteristics of the rotor airfoil is numerically investigated via numerical simulations of the unsteady Reynolds-averaged Navier-Stokes (URANS) equations coupled with the Spalart-Allmaras (S-A) turbulence model. The numerical methods are validated by a NACA0012 pitching airfoil case and a NACA6415 airfoil case based on the CFJ, and good agreement with experiments is found. Via the study of the typical conditions of CFJ control to suppress the dynamic stall of the OA212 rotor airfoil, it is verified that this method has a good effect on dynamic stall suppression. The diffusion and blending of the turbulent shear layer between the CFJ injection jet and the main flow excite the main flow and enhance its ability to resist the reverse pressure gradient; this suppresses the generation and development of the separation vortex, thereby enhancing the aerodynamic characteristics, improving the hysteresis effect, and increasing the system stability. On this basis, the control parameters of the CFJ are further studied, including the influences of the jet momentum coefficient and the positions and sizes of the injection and suction slots on suppressing the dynamic stall of the rotor airfoil. It is found that there is a jet momentum coefficient that optimizes the suppression effect of the dynamic stall of the rotor airfoil. Moreover, the position of the injection slot is found to have a greater effect on the dynamic stall suppression, while the size of the injection slot and the position and size of the suction slot have little effect.

中文翻译：

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基于同流射流的转子翼型失速动态控制研究

在这项研究中，将动态失速控制策略称为同流射流（CFJ），该策略应用于转子翼型。通过对非稳态雷诺平均Navier-Stokes（URANS）方程和Spalart-Allmaras（SA）湍流模型进行数值模拟，数值研究了CFJ对转子机翼非稳态动态失速特性的影响。通过基于CFJ的NACA0012俯仰翼型箱和NACA6415翼型箱对数值方法进行了验证，发现与实验吻合良好。通过研究CFJ控制的典型条件来抑制OA212转子翼型的动态失速，证明该方法对抑制动态失速具有良好的效果。CFJ射流和主流之间湍流剪切层的扩散和混合激发了主流并增强了其抵抗反向压力梯度的能力；这抑制了分离旋涡的产生和发展，从而增强了空气动力学特性，改善了滞后效应，并增加了系统稳定性。在此基础上，进一步研究了CFJ的控制参数，包括射流动量系数以及喷油口和吸油口的位置和尺寸对抑制转子翼型动态失速的影响。发现有一个射流动量系数，可以优化转子翼型动态失速的抑制效果。此外，