钝体尾迹的稳定性研究及流动控制探讨

On Stability Analyses of Wakes Behind Bluff Bodies and Flow Control

系统地回顾了研究钝体尾迹稳定性的主要方法，并利用局部绝对／对流稳定性分析及整体稳定性分析两种方法，研究了圆柱绕流定常和时均尾逆流场的稳定性。采用低维Galerkin方法数值研究了尾迹对圆柱流向振动的响应问题，揭示了频率锁定、涡街的激发和抑制等现象。首次用Floquet理论研究了流向振动圆柱尾迹的稳定性，证明了圆柱振动激发涡街的机理是典型的参数共振。此外还探讨了流动控制问题。

In this paper stability analysis methods of wakes behind bluff bodies are reviewed. Two approaches including local absolute/convective instability analysis and global instability analysis are used to investigate the stability of steady and time-average wake flows behind a stationary circular cylinder. Phenomena in flow around an in-line oscillating circular cylinder such as frequency lock-in, excitation and suppression of the vortex street are numerically studied by a low-dimensional Galerkin method. The first Floquet stability analyses of flows around anin-line oscillating circular cylinder show that the excitation of the vortex street results from a typical parametric resonance. In addition, flow control problems are discussed.