Daubersies L, Salmon J-B
Univ. Bordeaux, CNRS, Rhodia, LOF, UMR 5258, F-33680 Pessac, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Sep;84(3 Pt 1):031406. doi: 10.1103/PhysRevE.84.031406. Epub 2011 Sep 20.
We present a model that describes the drying of solutions and colloidal dispersions from droplets confined between two circular plates. This confined geometry, proposed by Clément and Leng [Langmuir 20, 6538 (2004)], casts a perfect control of the evaporation conditions, and thus also of the concentration kinetics of the solutes in the droplet. Our model, based on simple transport equations for binary mixtures, describes the concentration process of the solute inside the droplet. Using dimensionless units, we identify the different numbers that govern the concentration field of the solute, and we detail how to extract kinetic and thermodynamic information on the binary mixture from such drying experiments. We finally discuss, using numerical resolution of the model and analytical arguments, several specific cases: dilute solutions, a colloidal hard sphere dispersion, and a binary molecular mixture.
我们提出了一个模型，该模型描述了限制在两个圆形板之间的液滴中溶液和胶体分散体的干燥过程。这种由克莱门特和伦格[《朗缪尔》20, 6538 (2004)]提出的受限几何结构，能够对蒸发条件进行完美控制，进而也能对液滴中溶质的浓缩动力学进行完美控制。我们的模型基于二元混合物的简单输运方程，描述了液滴内部溶质的浓缩过程。使用无量纲单位，我们确定了控制溶质浓度场的不同数值，并详细说明了如何从此类干燥实验中提取二元混合物的动力学和热力学信息。最后，我们使用该模型的数值解和分析论证来讨论几个具体案例：稀溶液、胶体硬球分散体和二元分子混合物。
