近壁区湍能耗散率输运方程的理论模型

提出在湍流边界层的近壁区采用三维不稳定波来描述湍流扰动速度,然后根据理论模型对湍能耗散率的生成、粘性破坏以及扩散等特性进行了系统定量的计算和分析.理论计算结果与直接数值模拟结果符合较好,特别是在y<10的区域中明显优于传统湍流模型的计算结果.这不仅在理论上有益于对湍流物理机制的了解,而且可能为湍流模型计算开辟一条新的途径.

Theoretical Model for Dissipation-Rate Budgets in Near-WallRegion of a Turbulent Boundary Layer

Based on the linear hydrodynamic stability theory, a 3 D theoretical model is proposed for the turbulent fluctuations in near wall region of a turbulent boundary layer. In accordance with the theoretical model, budgets of the the dissipation rate of turbulent kinetic energy are calculated and its production rate, dissipation and transport are evaluated. Good agreements between the theoretical results and those of DNS are obtained.Especially in the region of y +<10 ,the theoretical model is obviously superior to some coventional ones in predicting ability. It is not only beneficial to understanding the physics of turbulence but also, probably, opening a new way for developing turbulence modeling.