Applications of statistical mechanics in subcontinuum fluid dynamics

We show results of molecular dynamics studies of fluid flows in the Knudsen regime in which the mean free path is comparable to the system size. WE:el ucidate the boundary conditions at the wall-fluid interface in such flows a nd find scenarios envisioned by Maxwell. We also find scenarios which do no t agree with Maxwell's hypothesis. We focus primarily on the case of repuls ive walls and discuss similarities and differences in behavior when the wal l-fluid interaction is attractive or repulsive. Striking many body effects are found on increasing the fluid density as one interpolates between the d ilute gas and the dense fluid regimes. (C) 1999 Elsevier Science B.V. All r ights reserved.