Numerical Investigation on Mixing Efficiency and Exponential Fluid Stretching in Chaotic Mixing

• 作 者: 王林翔 路甬祥
• 出 处: Chinese Journal of Chemical Engineering
• 发表日期: 2000年03期
• 关键词: stretching chaotic mixing folding exponential dynamical trajectory curved variat

The stretching and folding of fluid element during chaotic mixing field is studied using numericalmethod.The chaotic mixing process is caused by periodic secondary flow in a twisted curved pipe.Using thenonlinear discrete velocity field as the dynamical system,the present study connects the fluid particle’s stretchingalong its trajectory in one period to a linearized time-varying variational equation.After numerical approximationof the variational equation,fluid stretching is calculated on the whole cross section.The stretching distributionshows an exponential fluid stretching and folding,which indicates an excellent mixing performance.

The stretching and folding of fluid element during chaotic mixing field is studied using numerical method. The chaotic mixing process is caused by periodic secondary flow in a twisted curved pipe. Using then-linear discrete velocity field as the dynamical system, the present study connects the fluid particle’s stretchingalong its trajectory in one period to a linearized time-varying variational equation. A past numerical approximation of the variational equation, fluid stretching is calculated on the whole cross section. stretching tension shold an exponential fluid stretching and folding, which indicates an excellent mixing performance.