Borcia Rodica, Borcia Ion Dan, Bestehorn Michael
Lehrstuhl Statistische Physik, Nichtlineare Dynamik Brandenburgische Technische Universität, Cottbus, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Dec;78(6 Pt 2):066307. doi: 10.1103/PhysRevE.78.066307. Epub 2008 Dec 16.
We propose a scheme for studying thin liquid films on a solid substrate using a phase field model. For a van der Waals fluid-far from criticality-the most natural phase field function is the fluid density. The theoretical description is based on the Navier-Stokes equation with extra phase field terms and the continuity equation. In this model free of interface conditions, the contact angle can be controlled through the boundary conditions for the density field at the solid walls [L. M. Pismen and Y. Pomeav, Phys. Rev. E 62, 2480 (2000)]. We investigate the stability of a thin liquid film on a flat homogeneous solid support with variable wettability. For almost hydrophobic surfaces, the liquid film breaks up and transitions from a flat film to drops occur. Finally, we report on two-dimensional numerical simulations for static liquid drops resting on a flat horizontal solid support and for drops sliding down on inclined substrates under gravity effects.
我们提出了一种使用相场模型研究固体基底上薄液膜的方案。对于远离临界点的范德华流体，最自然的相场函数是流体密度。理论描述基于带有额外相场项的纳维 - 斯托克斯方程和连续性方程。在这个无需界面条件的模型中，接触角可以通过固体壁处密度场的边界条件来控制[L.M. 皮斯门和Y. 波米亚夫，《物理评论E》62，2480（2000）]。我们研究了具有可变润湿性的平坦均匀固体支撑物上薄液膜的稳定性。对于几乎疏水的表面，液膜会破裂并发生从平膜到液滴的转变。最后，我们报告了二维数值模拟结果，内容涉及静置在平坦水平固体支撑物上以及在重力作用下沿倾斜基底下滑的静态液滴。
