Hybrid Atomistic-Continuum Fluid Mechanics

T. Werder, J.H. Walther, E. Kotsalis, P. Gonnet and P. Koumoutsakos
ETH Zurich, CH

Keywords: multiscale algorithm, molecular dynamics, fluid dynamics

Abstract:
We outline a multiscale algorithm for the simulation of dense uids that couples molecular dynamics and continuum fluid dynamics. The coupling between the two models is realized by a common overlap domain and by the alternating Schwarz method. We prefer this method to those based on direct flux exchange, since the accurate estimation of the fluxes requires much more statistics. The boundary conditions on the atomistic region are imposed using stochastic walls to thermalize and confine the molecular dynamics system, and the usher algorithm to insert new atoms. The forcing of the continuum is achieved using appropriate source terms in the momentum equations. To test the algorithm, we study equilibrium liquid argon systems and the flow of liquid argon past a carbon nanotube.

Nanotech 2004 Conference Technical Program Abstract