The molecular simulation approach to complex hydrodynamics

We present here some recent results obtained in the direct simulation of nonequilibrium fluids. First, the transition to convection is studied by means of a hard‐disk model with the appropriate boundary conditions. The quantitative agreement between molecular dynamics and Navier–Stokes hydrodynamics is an impressive argument in favor of the hydrodynamic modeling down to atomic scales, even in nonequilibrium states. Next, the Rayleigh–Brillouin spectrum of a hard‐sphere fluid subjected to a temperature gradient is presented. The simulation is used as a quantitative test of the “Landau–Lifshitz” hypothesis concerning the amplitude of the fluctuating hydrodynamic fluxes, extended to nonequilibrium. Finally, a short description of shock waves in a dilute system is given and the discrepancy between the molecular simulations and the continuum approach is further discussed. We conclude by some remarks concerning the perspectives in nonequilibrium fluids offered by the development of large‐scale computers. © 1993 John Wiley & Sons, Inc. Copyright © 1993 John Wiley & Sons, Inc.SCOPUS: ar.jFLWNA