中文摘要：

采用基于SST κ-ω湍流模型耦合延迟脱体涡模拟技术（Delayeddetached-eddy simulation，DDES）的SST—DDES模型，数值求解Navier-Stokes方程。并针对低速流动问题，发展了基于隐式双时间步方法的低速预处理技术，用于数值模拟低速、高雷诺数湍流大分离流动问题。数值模拟了低速大迎角三角翼绕流及大迎角6：1椭球绕流，观察到与物理现象相一致的旋涡特征，且得到的定量数值结果与实验数据相吻合。

英文摘要：

The numerical method for solving Navier-Stokes equations is developed based on the SST κ-ω turbulence model and the delayed detached-eddy simulation（DDES）. Meanwhile, the preconditioning technique coupled with implicit dual time stepping approach is implemented to simulate large separated flows with low speed and high Reynolds number. Low speed flow over a delta wing and separation flows around a 6：1 prolate spheroid are simulated. The simulated complex vortex structures agree well with physical analyzed results and experimental data.