A slip model with molecular dynamics

Abstract

In this paper we present analytical investigations of the slip flow in a hard disk drive where the flying head is approximately 25 nm above the rotating disk. A new slip velocity model is developed, incorporating molecular dynamics to take into account the impact of molecular collisions which play an important role in the interactions between molecules and the solid surface. A modified Reynolds equation is derived based on the modified slip model. Analytical solutions for velocity distribution and flow rate, using the modified Reynolds equation are obtained. Non-dimensional flow rate for plane Poiseuille flow, pressure distributions and load-carrying capacities for slope flow are compared with those available in the literature. Comparison with first-order, second-order and 1.5-order slip models shows that the new model agrees reasonably well with the solution obtained from the linearized Boltzmann equation.