A generalized model for probing frictional characteristics of pressure-driven liquid microflows

In this article, a fundamental model was postulated to capture the influences of microfabrication characteristics on the frictional behavior of pressure-driven liquid microflows through a detailed analysis of the underlined surface effects that effectively link up these two strongly correlated aspects. For theoretical analysis, a continuum-based generalized formalism was derived for critically assessing the competing aspects of the stick-slip influences of the surface roughness elements, the randomness related to the spontaneous production, size distribution and coverage of the nanobubble layers, and the consequent apparent slip mechanisms due to hydrophobic interactions. Uncertainties pertaining to surface texture were accounted for by employing a stochastic version of the Navier-Stokes equation. The theoretical formulation was simultaneously validated with the data obtained from indigenous experiments and other benchmark studies reported in the literature and excellent quantitative trends in this regard were obtained for all cases. (C) 2007 American Institute of Physics.