细长体截面绕流中的一种临界状态

基金项目: 国家自然科学基金资助项目(10172017);航空基础科学基金资助项目(02A51048)

A Critical Pattern of Crossflow Around a Slender

Institute of Fluid Mechanics, Beijing University of Aeronautics and Astronautics, Beijing 100083, P. R. China

摘要: 应用拓扑分析的方法研究了细长体截面绕流拓扑结构的演变过程．指出随着细长体背涡的发展，导致截面流场的拓扑结构发生变化，会出现一种临界流动状态．在这种临界流态下，流场中会出现一种高阶奇点．这种高阶奇点的指数为-3/2．这种高阶奇点是结构不稳定的，稍有扰动就会产生分叉，使流场的拓扑结构发生变化．
- 细长体 /
- 高阶奇点 /
- 分叉 /
- 结构稳定性
Abstract: Topological structure of a slender crossflow was discussed with topological analysis.It is pointed that the development of slender vortices leads to the change of topological structure about cross flow,and a critical flow pattern will appear.There is a high-order singular point in this critical flow pattern.And the index of the high-order singular is -3/2.The topological structure of this singular point is instable,so bifurcation will occur and the topological structure of flowfield will be changed by little disturbance.
- slender /
- high-order singular point /
- bifurcation /
- structure stability

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