细长体绕流tertiary涡的形成与非对称过程

为探讨现代飞行器非对称流动中主涡的形成机理,利用染色线显示和荧光诱导激光片光技术,在北京航空航天大学1.2m水洞对细长体绕流过程进行了实验研究。结果表明,亚临界Re和大迎角零侧滑绕流时,细长体流场呈现复杂的非对称多涡流动现象。随着主涡的生成和发展,在模型背风侧再分离区诱导出一些次生结构,tertiary涡就是其中一种。沿着轴向,主涡发展成熟并依次脱落形成脱体涡,从主涡脱落点也依次产生新生主涡。其中,第1个新生涡由tertiary涡发展而来,而第2个和第3个新生涡则主要由分离剪切层卷绕生成。该文提出了tertiary涡演化为新生主涡的观点。

Formation of tertiary vortex and dynamical process of vortics asymmetric around a slender body

To study the generation mechanism of asymmetric vortices flow over modern flight vehicle, the dynamical process of vortices flow around rocket-shaped cylinder was studied experimentally using streak and laser-induced fluorescence techniques in a 1.2-m water tunnel of Beijing University of Aeronautics and Astronautics. Complicated asymmetric vortices flow is generated over the body at high incidences, zero sideslip and subcritical Reynolds number. With the generation and development of the main vortices, kinds of sub-structures are induced at the re-separation region on the leeward of the body including tertiary vortex. Along the axial direction, the main vortex fully develops and breaks away from the body, and a new main vortex generates in succession. The results indicate that the first new main vortex develops from tertiary vortex, while the second and the third new main vortices generate principally from the rolling-up of the separated shear layer. A new viewpoint that the tertiary vortex develops into the new main vortex is presented in this paper.