Modeling of Micro-Particle’s Motion Near an Evaporating Meniscus
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摘要: 蒸发弯月面附近存在复杂的流动结构.该文建立数值模型以精确模拟蒸发弯月面附近的传热传质过程并描绘液体中微小颗粒的运动轨迹.一方面,将弯月面上的蒸发、气相中的蒸汽扩散以及蒸发导致的界面冷却效果耦合求解.同时利用离散元方法(DEM)对颗粒在流体中的运动及其对流场的反作用进行耦合求解.通过与实验对比,该计算方法能够准确地描述弯月面附近的微颗粒运动轨迹.Abstract: The transport process and flow structure near an evaporating meniscus are highly complicated due to various coupling factors. A numerical model was developed to describe the physical process and motion of a micro-particle near an evaporating meniscus. The evaporation and its cooling effect on the interface, vapor diffusion in the gas domain, as well as thermocapillary flow were considered together with computational fluid dynamics (CFD). At the same time, the particle’s motion was tracked with discrete element method (DEM). The interaction between the micro flow field and the particle, including drag force and buoyancy force, was considered. The simulation results agree well with the experiments in previous published literatures.
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Key words:
- evaporation /
- meniscus /
- thermocapillary flow /
- micro-particle /
- microfluidics
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