Dissipative particle dynamics with attractive and repulsive particleparticle interactions
Abstract
In molecular dynamics simulations, a combination of shortrange repulsive and longrange attractive interactions allows the behavior of gases, liquids, solids, and multiphase systems to be simulated. We demonstrate that dissipative particle dynamics (DPD) simulations with similar pairwise particleparticle interactions can also be used to simulate the dynamics of multiphase fluids. In these simulations, the positive, shortrange, repulsive part of the interaction potentials were represented by polynomial spline functions such as those used as smoothing functions in smoothed particle hydrodynamics, and the negative longrange part of the interaction has the same form but a different range and amplitude. If a single spline function corresponding to a purely repulsive interaction is used, the DPD fluid is a gas, and we show that the Poiseuille flow of this gas can be described accurately by the NavierStokes equation at low Reynolds numbers. In a twocomponent system in which the purely repulsive interactions between different components are substantially larger than the purely repulsive intracomponent interactions, separation into two gas phases occurs, in agreement with results obtained using DPD simulations with standard repulsive particleparticle interactions. Finally, we show that a combination of shortrange repulsive interactions and longrange attractive interactions can be used to simulate the behaviormore »
 Authors:
 Publication Date:
 Research Org.:
 Idaho National Laboratory (INL)
 Sponsoring Org.:
 DOE  EM
 OSTI Identifier:
 912372
 Report Number(s):
 INL/JOU0500242
TRN: US0800365
 DOE Contract Number:
 DEAC0799ID13727
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Fluids; Journal Volume: 18; Journal Issue: 1
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72  PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; FLUID FLOW; FRACTURES; GASES; HYDRODYNAMICS; LAMINAR FLOW; NAVIERSTOKES EQUATIONS; POLYNOMIALS; REYNOLDS NUMBER; SPLINE FUNCTIONS; DPD; interactions; molecular; multiphase systems; particleparticle interactions
Citation Formats
Paul Meakin, Moubin Liu, and Hai Huang. Dissipative particle dynamics with attractive and repulsive particleparticle interactions. United States: N. p., 2006.
Web.
Paul Meakin, Moubin Liu, & Hai Huang. Dissipative particle dynamics with attractive and repulsive particleparticle interactions. United States.
Paul Meakin, Moubin Liu, and Hai Huang. Sun .
"Dissipative particle dynamics with attractive and repulsive particleparticle interactions". United States.
doi:.
@article{osti_912372,
title = {Dissipative particle dynamics with attractive and repulsive particleparticle interactions},
author = {Paul Meakin and Moubin Liu and Hai Huang},
abstractNote = {In molecular dynamics simulations, a combination of shortrange repulsive and longrange attractive interactions allows the behavior of gases, liquids, solids, and multiphase systems to be simulated. We demonstrate that dissipative particle dynamics (DPD) simulations with similar pairwise particleparticle interactions can also be used to simulate the dynamics of multiphase fluids. In these simulations, the positive, shortrange, repulsive part of the interaction potentials were represented by polynomial spline functions such as those used as smoothing functions in smoothed particle hydrodynamics, and the negative longrange part of the interaction has the same form but a different range and amplitude. If a single spline function corresponding to a purely repulsive interaction is used, the DPD fluid is a gas, and we show that the Poiseuille flow of this gas can be described accurately by the NavierStokes equation at low Reynolds numbers. In a twocomponent system in which the purely repulsive interactions between different components are substantially larger than the purely repulsive intracomponent interactions, separation into two gas phases occurs, in agreement with results obtained using DPD simulations with standard repulsive particleparticle interactions. Finally, we show that a combination of shortrange repulsive interactions and longrange attractive interactions can be used to simulate the behavior of liquid drops surrounded by a gas. Similar models can be used to simulate a wide range of processes such as multiphase fluid flow through fractures and porous media with complex geometries and wetting behaviors.},
doi = {},
journal = {Physics of Fluids},
number = 1,
volume = 18,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

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