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Title: Dissipative particle dynamics with attractive and repulsive particle-particle interactions

Abstract

In molecular dynamics simulations, a combination of short-range repulsive and long-range 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 particle-particle interactions can also be used to simulate the dynamics of multiphase fluids. In these simulations, the positive, short-range, 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 long-range 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 Navier-Stokes equation at low Reynolds numbers. In a two-component 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 particle-particle interactions. Finally, we show that a combination of short-range repulsive interactions and long-range attractive interactions can be used to simulate the behaviormore » 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.« less

Authors:
; ;
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - EM
OSTI Identifier:
912372
Report Number(s):
INL/JOU-05-00242
TRN: US0800365
DOE Contract Number:
DE-AC07-99ID-13727
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; NAVIER-STOKES EQUATIONS; POLYNOMIALS; REYNOLDS NUMBER; SPLINE FUNCTIONS; DPD; interactions; molecular; multiphase systems; particle-particle interactions

Citation Formats

Paul Meakin, Moubin Liu, and Hai Huang. Dissipative particle dynamics with attractive and repulsive particle-particle interactions. United States: N. p., 2006. Web.
Paul Meakin, Moubin Liu, & Hai Huang. Dissipative particle dynamics with attractive and repulsive particle-particle interactions. United States.
Paul Meakin, Moubin Liu, and Hai Huang. Sun . "Dissipative particle dynamics with attractive and repulsive particle-particle interactions". United States. doi:.
@article{osti_912372,
title = {Dissipative particle dynamics with attractive and repulsive particle-particle interactions},
author = {Paul Meakin and Moubin Liu and Hai Huang},
abstractNote = {In molecular dynamics simulations, a combination of short-range repulsive and long-range 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 particle-particle interactions can also be used to simulate the dynamics of multiphase fluids. In these simulations, the positive, short-range, 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 long-range 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 Navier-Stokes equation at low Reynolds numbers. In a two-component 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 particle-particle interactions. Finally, we show that a combination of short-range repulsive interactions and long-range 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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  • The exact solution via Bethe's ansatz to a model consisting of two parabolic bands of electrons with local attractive and repulsive interactions is presented. Some low-temperature properties of this model are discussed as a function of the interaction strength, a magnetic field, and the crystal-field splitting between the bands. The attractive interaction leads to Cooper-pair-like bound states and a threshold magnetic field is required to overcome the binding energy. The low-{ital T} specific heat is proportional to {ital T}, except at critical points where {ital C}{proportional to}{ital T}{sup 1/2}.
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