脉动流速的分解和脉动应力探讨

本文用运动学观点,根据紊流的脉动性质,导出脉动流速的分解方程.此方程将脉动流速分解为三个组成部分,并且据此导出脉动应力分解方程.通过对脉动应力性质的分析,提出一些设想,于是将脉动应力的分解方程简化为三个组成部分,是推广Boussinesq J假设的合理修正和发展,可以用来作为求解紊流问题的基础.

Resolution of Fluctuating Velocity and Study of Renolds-Stress

From the viewpoint of kinetics and based on the fluctuating characteristics of turbulence, the fluctuating velocity is resolved into three parts and the composed eqution of fluctuating velocity is derived. According to the above work, the Renolds-stress is resolved into serval parts, and the composed equation of Renolds-stress is derived. Through the analysis of Renolds-stress properties, some hypotheses are proposed and the composed equation of Renolds-stress is simplified, in which only three parts are left. The simplified equation is the resonable modification and development of the extended Boussinesq J hypothesis and it can be used as the basis of solving turbulence problems.