采用μ-LIF技术可视化研究了微通道中液滴内部的组分混合行为,建立了描述多相多组分体系的格子Boltzmann方法 (LBM),通过μ-LIF实验确定了LBM模型关键参数,成功模拟了微通道中液滴内部的混合行为。研究表明,液滴在运动中发生形变可以有效缩短传质距离,实现强化混合的目的。同时,分散相对壁面的润湿性质对复杂结构微通道中液滴流动起着重要作用。所得结果为微尺度复杂流动行为的研究提供了理论基础。
Liquid mixing behavior inside micro-droplets in the microchannels was visualized by μ-LIF technique.These measurement results were used to validate the numerical simulations by a newly developed multi-phase,multi-component lattice Boltzmann method(LBM),especially to determine a key parameter in the LBM model.The results showed that the simulation could successfully reveal the detailed mixing phenomena inside the droplets.It was discovered that the droplet deformation along its movement in the microchannels could significantly shorten the distance of mass transfer,and thereafter intensify the mixing process.The wetting property of the dispersed phase had strong influence on the flow pattern when the droplet passed through the complex geometry of the micro-channels.In summary,this work provided a solid foundation for the theoretical investigation of complex flows in micro-reactors.