Université de Lyon, F-69000, Lyon, France.
J Chem Phys. 2011 Mar 7;134(9):094105. doi: 10.1063/1.3557061.
While the flow of a liquid in a macroscopic channel is usually described using hydrodynamics with no-slip boundary conditions at the walls of the channel, transport phenomena in microchannels involve physics at many different scales due to the interplay between the micrometric section of the channel and the micro- or nanometric roughness of the boundaries. Roughness can have many different effects such as increasing the friction between the liquid and the walls (leading to the macroscopic no-slip boundary condition) or on the contrary reduce it thanks to the Wenzel-Cassie-Baxter wetting transition induced by capillarity. Here we detail a phase-field/dynamic density functional theory model able to account for the wetting transitions, the resulting friction between the wall and the fluid, and compressible hydrodynamics at high viscosity contrast.
虽然宏观通道中的液体流动通常使用流体动力学来描述，并且通道壁的边界条件为无滑移，但由于通道的微观部分与边界的微观或纳米级粗糙度之间的相互作用，微通道中的输运现象涉及到许多不同尺度的物理现象。粗糙度会产生许多不同的影响，例如增加液体与壁之间的摩擦力（导致宏观无滑移边界条件），或者相反地，由于毛细作用引起的 Wenzel-Cassie-Baxter 润湿转变而减小摩擦力。在这里，我们详细介绍了一个能够考虑润湿转变、壁面与流体之间的摩擦力以及高粘度对比下可压缩流体动力学的相场/动态密度泛函理论模型。
