Wetting: Inverse Dynamic Problem and Equations for Microscopic Parameters.
Wetting: Inverse Dynamic Problem and Equations for Microscopic Parameters.
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DOI：
10.1006/jcis.2000.6726
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发表时间：
2000-06
影响因子：
9.9
通讯作者：
O. Voinov
中科院分区：
文献类型：
--
作者：
O. Voinov
考虑了液体半月板在小直径毛细管中填充或排空时的运动。这种液体不挥发。在低雷诺数和低毛细数条件下，研究了液气界面形状。这个边界与靠近接触线的固体的倾斜角很小。考虑了润湿动力学中的反问题：建立了影响三相接触线动力学的通用常数的解析表达式。推导了半月板在毛细管中运动的实验中得到的宏观测量值与微观参数的反比关系。反比关系得到了独立的证明。为此，采用德热纳的部分润湿模型，对范德华液体进行了数值实验。微参数的一般公式与数值实验结果吻合较好。本文给出了影响范德华液体半月板润湿性的相似判据。求解了前进半月板和后退半月板的逆动力学问题。提出了半月板衰退临界速度的关系式。讨论了半月板的两个接触角。研究了临界转速附近动态接触角的变化规律。其中一个角在小于临界速度时消失，而另一个角正好在临界速度时消失。在前进半月板的情况下，微参数方程对部分润湿和完全润湿都有效。提出的完全润湿的逆表达式可以确定最大前驱膜厚度及其对运动速度的依赖（也可以确定范德华液体情况下的Hamaker常数）。学术出版社版权所有。
Movement of a liquid meniscus in a low-diameter capillary while it is being filled or emptied is considered. The liquid is nonvolatile. Assuming low Reynolds number and low capillary number, the liquid-gas interface shape is studied. Angles of inclination of this boundary to the solid near the contact line are small. Consideration is given to the inverse problem in wetting dynamics: to establish an analytic expression for the universal constant that influences the dynamics of a three-phase contact line. Inverse relations for microscopic parameters in terms of macroscopic measured values obtained in experiments with a meniscus moving through a capillary are derived. The inverse relations are substantiated independently. To do so, numerical experiments for a van der Waals liquid have been carried out, using the de Gennes model of partial wetting. General formulas for microparameters agree well with numerical experiments. The article provides the similarity criterion which influences the wetting in the case of a van der Waals liquid meniscus. The inverse dynamic problem for both an advancing and a receding meniscus is solved. A relation for the critical speed of meniscus recession is proposed. Two contact angles for a meniscus are discussed. Behavior of dynamic contact angles in the vicinity of the critical speed is studied. One of the angles is shown to vanish at less than the critical speed, and the other one, exactly at the critical speed. In the case of an advancing meniscus the equations for microparameters are valid for both partial and complete wetting. The proposed inverse expression for complete wetting allows determination of the maximum precursor film thickness and its dependence on the motion speed (also determination of the Hamaker constant in the case of a van der Waals liquid). Copyright 2000 Academic Press.