摘要
阻力的精确计算,一直是低雷诺数飞行器设计的关键。而与附面层分离和转捩相关的摩擦阻力的精确计算则是此类飞行器阻力精确计算的关键。因此,开展了基于湍流模型的转捩预测方法的研究,应用几种湍流模型对平板边界层进行计算分析,研究各湍流模型预测流动转捩的能力。由于各模型对扰动的过于敏感,引起转捩提前发生,使预测与实验差距较大,由于k-ωSST两方程湍流模型预测能力优于其它模型,在此模型基础上引入了间隙函数进行粘性系数修正,对平板和NACA 0012翼型的转捩重新进行了预测,计算结果表明改进后的模型对转捩位置具有较好预测能力。
The accurate prediction of drag is key to the design of the low Reynold＇s number flight vehicle, and the accurate prediction of friction drag which is induced by separation and transition of the boundary layer is key to the accurate prediction of drag. In this paper, numerical method based on turbulence model to predict flow transition is studied. For researching the ability of transition prediction, the plate boundary layer is calculated and analyzed by using some turbulent model. These turbulent models are so sensitive to the perturbation that causes the transition to occur ahead of time and the difference between prediction and experiment, therefore, a modified k- ω SST two- equation model taking account of intermittence function effect is put forward. By using this modified k- ω SST model to simulate the flat plate boundary layer and the flow past NACA0012, it is seen that the modified model can predict the transition position with certain accuracy.
出处
《航空计算技术》
2008年第3期39-41,共3页
Aeronautical Computing Technique
关键词
转捩
湍流模型
k-ωSST两方程湍流模型
附面层
transition
turbulence model
k-ω SST two-equation turbulence model
boundary layer
