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arXiv · 0903.0485

On the microscopic foundation of dissipative particle dynamics

Anders Eriksson·Martin Nilsson Jacobi·Johan Nystrom·Kolbjorn Tunstrom
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Abstract

Mesoscopic particle based fluid models, such as dissipative particle dynamics, are usually assumed to be coarse-grained representations of an underlying microscopic fluid. A fundamental question is whether there exists a map from microscopic particles in these systems to the corresponding coarse-grained particles, such that the coarse-grained system has the same bulk and transport properties as the underlying system. In this letter, we investigate the coarse-graining of microscopic fluids using a Voronoi type projection that has been suggested in several studies. The simulations show that the projection fails in defining coarse-grained particles that have a physically meaningful connection to the microscopic fluid. In particular, the Voronoi projection produces identical coarse-grained equilibrium properties when applied to systems with different microscopic interactions and different bulk properties.

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Anders Eriksson, Martin Nilsson Jacobi, Johan Nystrom, Kolbjorn Tunstrom. 2009-03-03. On the microscopic foundation of dissipative particle dynamics. https://doi.org/10.1209/0295-5075/86/44001

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