Slippery hydrodynamics in grooved hydrophobic microchannels is known to be primarily dictated by the area of the gas–liquid contact surface. Here, we augment this classical notion by bringing out the critical role played by the channel dimensions on the underlying slip mechanisms and the consequent drag reduction. Our analysis, towards this, reveals the non-trivial implication of gas–liquid interface topology and its position inside the groove towards dictating the underlying frictional characteristics, which in turn is largely dependent on the confluence of the channel hydraulic diameter and the groove width. These results may turn out to be of immense consequence towards arriving at preferred frictional drag characteristics of hydrophobic microchannels and nanochannels by judicious choices of the pertinent geometric parameters.

已知有沟槽的疏水性微通道中的滑流动力学主要取决于气液接触面的面积。在这里，我们通过揭示通道尺寸在基础滑移机制上所起的关键作用以及随之而来的减阻作用来增强这一经典概念。为此，我们的分析揭示了气液界面拓扑的重要意义及其在沟槽内的位置，以决定潜在的摩擦特性，而摩擦特性又主要取决于通道水力直径和沟槽宽度的融合。这些结果可能变成是巨大后果的朝向在由相关的几何参数的明智选择疏水微通道和纳米通道的优选摩擦阻力特性到达。