On evaporation of sessile drops with moving contact lines
On evaporation of sessile drops with moving contact lines
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DOI：
10.1017/jfm.2011.133
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发表时间：
2011-07-01
影响因子：
3.7
通讯作者：
Kondic, L.
中科院分区：
文献类型：
--
作者：
Murisic, N.;Kondic, L.
我们从理论上、计算上和实验上考虑了水和异丙醇液滴在光滑硅片上的自发蒸发。与以往的一些工作不同，我们考虑的固体表面是光滑的，因此液滴的演化没有接触线钉扎。我们建立了一个纯液滴蒸发的理论模型，该模型考虑了非均匀蒸发产生的温度梯度所产生的Marangoni力，以及液、固两相的热传导效应。该模型中的关键成分是蒸发通量。我们考虑了两种常用的模型：一种基于假设蒸发受源自气体的过程的限制(蒸汽扩散限制蒸发)，另一种基于假设液体中的过程是有限的。我们的理论模型允许实现由这两种方法产生的蒸发通量。所需参数是从物理实验中获得的。然后，我们进行了完全非线性的时间相关模拟，并将结果与实验结果进行了比较。最后，我们讨论了如何使用模拟结果来预测两个理论模型中的哪一个适合于特定的物理实验。
We consider theoretically, computationally and experimentally spontaneous evaporation of water and isopropanol drops on smooth silicon wafers. In contrast to a number of previous works, the solid surface we consider is smooth and therefore the droplets' evolution proceeds without contact line pinning. We develop a theoretical model for evaporation of pure liquid drops that includes Marangoni forces due to the thermal gradients produced by non-uniform evaporation, and heat conduction effects in both liquid and solid phases. The key ingredient in this model is the evaporative flux. We consider two commonly used models: one based on the assumption that the evaporation is limited by the processes originating in the gas (vapour diffusion-limited evaporation), and the other one which assumes that the processes in the liquid are limiting. Our theoretical model allows for implementing evaporative fluxes resulting from both approaches. The required parameters are obtained from physical experiments. We then carry out fully nonlinear time-dependent simulations and compare the results with the experimental ones. Finally, we discuss how the simulation results can be used to predict which of the two theoretical models is appropriate for a particular physical experiment.