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DOE OSTI · 1511269

Coarse-Grained Hydrodynamics from Correlation Functions

Palmer, Bruce J.
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Abstract

This paper will describe a formalism for using correlation functions between different grid cells as the basis for determining coarse-grained hydrodynamic equations for modeling the behavior of mesoscopic fluid systems. Configurations from a molecular dynamics simulation or other atomistic simulation are projected onto basis functions representing grid cells in a continuum hydrodynamic simulation. Equilibrium correlation functions between different grid cells are evaluated from the molecular simulation and used to determine the evolution operator for the coarse-grained hydrodynamic system. The formalism is demonstrated on a discrete particle simulation of diffusion with a spatially dependent diffusion coefficient. Correlation functions are calculated from the particle simulation and the spatially varying diffusion coefficient is recovered using a fitting procedure.

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BibTeXRIS

Palmer, Bruce J.. 2018-02-06. Coarse-Grained Hydrodynamics from Correlation Functions. https://doi.org/10.1103/physreve.97.022106

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