摘要
为了改善高超声速进气道在低马赫数下的自起动能力,设计了一种高超声速进气道电磁流动加速控制方案.基于低磁雷诺数假设建立完全气体湍流流场、电磁场耦合数值计算方法,数值分析了不同外加电磁场条件下进气道加速起动过程中流场结构、起动特性控制效果.结果表明:施加外加磁场、电场后,洛伦兹力的方向和流动方向相同,此时控制区域洛伦兹力起到加速的作用,增加了近壁面流体的动量,从而增强边界层抵抗分离的能力;此外,顺流向洛伦兹力增加了壁面的剪切应力,从而增加局部湍流流场壁面摩擦阻力系数;背景进气道不起动状态存在大规模分离区,电场、磁场作用下,分离泡受到额外的顺流向洛伦兹力作用,为达到分离区受力平衡,压力平台区域变小,宏观体现为分离点后移,分离泡尺度减小;加速起动过程中,顺流向洛伦兹力可以降低背景进气道自起动马赫数,拓宽进气道工作马赫数范围.
Numerical simulations of a generic hypersonic inlet were conducted under the influence of an external electromagnetic field to demonstrate the feasibility of enlarging the envelope of self-starting operation.Numerical and analytical models of self-starting ability control in an electromagnetically controlled inlet were established.The analysis demonstrates that the performance of electromagnetic boundary layer flow control is mainly determined by the Lorentz force in the flow direction by applying an external electromagnetic field.Moreover,the low-velocity fluid in the boundary layer can be accelerated,thus enhancing the ability of the boundary layer to resist separation.Furthermore,the Lorentz force in the streamwise direction could increase the shear stress and the skin friction coefficient.The most prominent characteristic of the unstarted inlet flowfield is the large-scale separation bubble.With an external electromagnetic field applied,the separation bubble is subjected to additional streamwise Lorentz forces.To maintain force balance at the separation zone,the pressure plateau decreases,and the location of the separation point moves downstream,resulting in a decrease in the size of the separation bubble.During the accelerating start process,the Lorentz force directed along the stream can reduce the self-starting Mach number of the background inlet,thereby expanding the operating Mach range remarkably.
作者
罗仕超
柳军
胡守超
吴里银
常雨
孔小平
张宏安
吕明磊
LUO ShiChao;LIU Jun;HU ShouChao;WU LiYin;CHANG Yu;KONG XiaoPing;ZHANG HongAn;LV MingLei(Hypervelocity Aerodynamics Institute,China Aerodynamics Research and Development Center,Mianyang 621000,China;Laboratory of Aerodynamics in Multiple Flow Regimes,China Aerodynamics Research and Development Center,Mianyang 621000,China;College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China)
出处
《中国科学：物理学、力学、天文学》
CSCD
北大核心
2024年第3期134-145,共12页
Scientia Sinica Physica,Mechanica & Astronomica
基金
国家重点研发计划(编号:2019YFA0405200,2019YFA0405300)资助。
