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利用DES方法对处于非对称流态下的细长旋成体进行了俯仰和偏航振荡的数值模拟,观察细长体气动特性尤其是背风面非对称分离涡的变化。计算结果表明在大迎角非对称多涡系情况下,固定频率和振幅的非定常运动可以改变流场结构和气动力,对细长体背风面流态有巨大的影响。俯仰振荡对非对称分离涡有明显的控制作用,抑制流场的非对称性,使分离涡趋于对称;而固定频率的偏航振荡则破坏背风面分离涡的稳定性,激励非对称背涡产生随时间变化的周期性脱落。所进行的非定常运动与细长体流场耦合作用研究在国内外研究尚少。
The aerodynamic characteristics of slender body, especially the leeward asymmetric separation vortex, were simulated by DES method under asymmetric flow regime. The calculation results show that the unsteady motion of fixed frequency and amplitude can change the structure of flow field and aerodynamic force in the case of asymmetric multi-vortex at high angle of attack, which has a huge impact on the leeward flow regime of slender body. Pitch oscillation has obvious control effect on the asymmetric separation vortex, which suppresses the asymmetry of the flow field and makes the separation vortex symmetrical. However, the yaw oscillation at the fixed frequency destroys the stability of the separation vortex on the leeward side and excites the asymmetric vortex Produces periodic exfoliation over time. The research on the coupling effect between unsteady flow and slender body flow field is still little at home and abroad.