周期性压力对T型微管内二元流体混合效果的影响

The effect of periodic forcing on mixing of binary fluids in the T-type micro channel

在微流动领域经常涉及到试剂的混合问题,但是在微设备中,雷诺数Re低,流体趋向于形成层流,很难发生有效的混合.通过对微管内流体施加周期性压力使流速随时间呈周期性变化可以有效促进微流动混合.运用格子Boltzmann方法模拟了T型微管内流体的流速随时间呈正弦曲线变化而导致的混沌现象.结果发现,混沌混合的效果取决于两流体流速的相位差、流速的变化周期和系统的雷诺数Re.

Many microfluidic applications required the mixing of reagents, and etticient mixing in these laminar （ i. e. , low Reynolds number） systems was typically difficult. Flow rate time dependency through periodic forcing offered an effective means to control fluid behavior and in turn to enhance mixing. It was numerically studied instantaneous flow rate which was sinusoidal with respect to time induced chaotic mixing in T-type micro channel by using lattice Boltzmann method. It was found that the effect of mixing depended on the phase difference between two fluids＇ velocity, the vibration frequency of velocity and the Reynolds number of the system.