2003/10/28 by Colin Denniston, Mark O. Robbins · 1 citation
Engineering · Physics and Astronomy · #Fluid Dynamics and Thin Films #Lattice Boltzmann Simulation Studies #Theoretical and Computational Physics #cond-mat.soft
paper · pdf · doi:10.1103/physreve.69.021505
43 pages, 17 figures, RevTex4
arxiv created 2003/10/28 · openalex publication_date 2004/02/25 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We map molecular dynamics simulations of fluid-fluid interfaces onto mesoscale continuum theories for partially miscible fluids. Unlike most previous work, we examine not only the interface order parameter and density profiles, but also the stress. This allows a complete mapping from the length scales of molecular dynamics simulations onto a mesoscale model suitable for a lattice Boltzmann or other mesoscale simulation method. Typical assumptions of mesoscale models, such as incompressibility, are found to fail at the interface, and this has a significant impact on the surface tension. Spurious velocities, found in a number of discrete models of curved interfaces, are found to be minimized when the parameters of the mesoscopic model are made consistent with molecular dynamics results. An improved mesoscale model is given and demonstrated to produce results consistent with molecular dynamics simulations for interfaces with widths down to near molecular size.