Simulation of Gas Film Lubrication in Magnetic Disc Storage: DSMC Method Coupled with a Continuum Solution

摘要

In the paper we present some results from Monte Carlo simulations of two-dimensional unsteady problem of gas flow in an extremely narrow channel with an inclined upper wall and moving lower one. This is a model of gas film lubrication which occurs in modern magnetic disk storage, now being under development. Due attention is given to nonuniform inner and outer structure of the boundary incoming and outgoing flows. This is accomplished by simultaneous continuum finite element solution for the outer flow around the magnetic head. The coupling of DSMC simulation with this continuum solution is realized as step by step approximation. It is found that the molecular density before and after the channel differs markedly from the atmospheric one because of the slowing down of the flow by magnetic head. Thus previously much used atmospheric pressure boundary conditions there are quite far from reality. Space and time distributions of different parameters of the flow are given.