中文摘要：

为研究细长体背风面非对称分离涡在俯仰振荡中的变化,选取2种典型细长体非对称流态的初始迎角,在固定振幅和频率的情况下,利用脱体涡模拟（Detached-Eddy Simulation,DES）方法对处于非对称流场下的细长旋成体进行数值模拟.计算结果表明,俯仰振荡对细长体背风面流态有巨大的影响,对非对称分离涡有明显的控制作用,在大迎角非对称涡系未破裂以及特大迎角非对称涡系依次破裂的情况下,俯仰振荡都可以改变流场结构,抑制流场的非对称性,使分离涡趋于对称.

英文摘要：

To study the separation vortex on the leeside of slender body at the time of pitching oscillation,the RANS/LES hybrid methods based on S-A model was presented to simulate separated flow at two typical starting angles of attack.The result shows that the pitching oscillation greatly affects the flow field around slender body;the pitching oscillation obviously control the asymmetry separation vortex.While multi asymmetric vortexes at high angle of attack don＇t break down and multi asymmetric vortexes break down in turn at extremely high angle of attack,the pitching oscillation has strong control ability,and the asymmetrical flow is restrained and tends to symmetrical flow.