Spreading Kinetics of Constrained Thin Films

约束薄膜的铺展动力学

• 批准号: 0228834
• 负责人: Parthasakha Neogi
• 金额: $ 11.18万
• 依托单位: Missouri University of Science and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0228834&HistoricalAwards=false
• 关键词: Spreading; Kinetics; Constrained; Thin; Films

Parthasakha NeogiU of Missouri - Rolla"Spreading Kinetics of Constrained Thin Films"The rate at which a liquid spreads over a solid surface is called the wetting kinetics, which deals with the rates at which a liquid moves over a solid surface and displaces a second fluid. Since the liquid film thickness gradually decreases to zero as the contact line, the line common to the solid-liquid-vapor phases, is approached, the special properties of thin liquid films play an important role. Of importance here is the disjoining pressure, which is related to the excess potential in thin films (less than 100 nanometers), and can be used as a body force to describe the hydrodynamics and equilibrium. This analytical research is for a liquid that has both attraction and repulsion for the solid substrate in its disjoining pressure, which is common but has not been analyzed. Although the thin film phenomenon determines that the liquid is non-wetting, the dynamics of spreading itself seems unaffected in the experiments by the disjoining pressure until the time when the moving liquid suddenly equilibrates. A quantitative description of how such a behavior arises will be made clear from the results of this research. The fluid mechanical equations for the profile of the moving liquid film will be solved numerically. The numerical method is made very difficult by the need to look at two very different length scales, the scale of the basic liquid mass and the thin film dimensions, and over very long times. Additionally, the effect of liquid evaporation and surface roughness will be considered, since they bring in great deal of reality to the analysis.

密苏里州罗拉大学的Parthasakha NeogiU的《受限薄膜扩散动力学》液体在固体表面上扩散的速度被称为润湿动力学，它研究的是液体在固体表面上移动并置换第二种液体的速度。由于液膜厚度作为接触线逐渐减小到零，即接近固-液-气三相的共线，因此，液膜的特殊性质起着重要的作用。这里重要的是分离压力，它与薄膜中的过剩电势(小于100纳米)有关，可以作为体力来描述流体动力学和平衡。这项分析研究是针对一种液体，这种液体在其分离压力下对固体基质既有吸引又有排斥，这种情况很常见，但还没有被分析过。尽管薄膜现象决定了液体是非润湿的，但在实验中，分离压力似乎不会影响扩散本身的动力学，直到移动的液体突然平衡为止。从这项研究的结果将清楚地定量描述这种行为是如何产生的。运动液膜轮廓的流体力学方程将被数值求解。由于需要观察两个非常不同的长度尺度，基本液体质量尺度和薄膜尺寸，以及非常长的时间，使得数值方法变得非常困难。此外，还将考虑液体蒸发和表面粗糙度的影响，因为它们为分析带来了大量的实际情况。