针对传统概念设计的蛇形进气道畸变大、总压恢复系数较低以及相应流场控制技术存在局限性等缺点,对典型蛇形进气道内通道二次流的涡动力学形成及其对气流分离影响分析的基础上,提出了蛇形进气道涡控设计概念,并利用数值仿真进行了初步验证。仿真结果表明:与原型方案相比,蛇形进气道涡控设计方案成功抑制了上壁面大范围的气流分离,巡航状态畸变指数DC60降低了76%,总压恢复系数提高了0.84%,并且能够在较宽广的飞行包线内以较高的性能安全工作,表明了涡控设计概念的可行性。同时,由于涡控设计概念无需添加任何辅助的流场控制措施,因此有望使蛇形进气道迈向工程实用。
To deal with the low total pressure recovery rate and the high distortion level of serpentine inlets designed with the traditional method, a novel design concept of serpentine inlets based on surface vortex controlled global secondary flow reconstruction is presented in this paper. The simulation validation for the concept shows that:1) the vortex-controlled model successfully alleviates the large separation occurring on the top surface of the baseline model, which is because the vortex induced by the vortex-controlled design rotates in a direction opposite to that of the baseline vortex responsible for the separation; 2) the vortex-controlled model reduces circumferential distortion (as calculated by the DC60 descriptor) by 76% while improving the total pressure recovery by 0.84%. These results demonstrate the feasibility of the vortex-controlled design concept for serpentine inlets.
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