Momentum conserving Brownian dynamics propagator for complex soft matter fluids
Abstract
We present a Galilean invariant, momentum conserving first order Brownian dynamics scheme for coarsegrained simulations of highly frictional soft matter systems. Friction forces are taken to be with respect to moving background material. The motion of the background material is described by locally averaged velocities in the neighborhood of the dissolved coarse coordinates. The velocity variables are updated by a momentum conserving scheme. The properties of the stochastic updates are derived through the ChapmanKolmogorov and FokkerPlanck equations for the evolution of the probability distribution of coarsegrained position and velocity variables, by requiring the equilibrium distribution to be a stationary solution. We test our new scheme on concentrated star polymer solutions and find that the transverse current and velocity time autocorrelation functions behave as expected from hydrodynamics. In particular, the velocity autocorrelation functions display a long time tail in complete agreement with hydrodynamics.
 Authors:
 Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven (Netherlands)
 Computational Biophysics, University of Twente, P.O. Box 217, 7500 AE Enschede (Netherlands)
 Publication Date:
 OSTI Identifier:
 22415405
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 24; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BROWNIAN MOVEMENT; CORRELATION FUNCTIONS; EQUILIBRIUM; FLUIDS; FOKKERPLANCK EQUATION; FRICTION; HYDRODYNAMICS; MATHEMATICAL SOLUTIONS; POLYMERS; PROBABILITY; PROPAGATOR; STOCHASTIC PROCESSES; VELOCITY
Citation Formats
Padding, J. T., and Briels, W. J.. Momentum conserving Brownian dynamics propagator for complex soft matter fluids. United States: N. p., 2014.
Web. doi:10.1063/1.4904315.
Padding, J. T., & Briels, W. J.. Momentum conserving Brownian dynamics propagator for complex soft matter fluids. United States. doi:10.1063/1.4904315.
Padding, J. T., and Briels, W. J.. 2014.
"Momentum conserving Brownian dynamics propagator for complex soft matter fluids". United States.
doi:10.1063/1.4904315.
@article{osti_22415405,
title = {Momentum conserving Brownian dynamics propagator for complex soft matter fluids},
author = {Padding, J. T. and Briels, W. J.},
abstractNote = {We present a Galilean invariant, momentum conserving first order Brownian dynamics scheme for coarsegrained simulations of highly frictional soft matter systems. Friction forces are taken to be with respect to moving background material. The motion of the background material is described by locally averaged velocities in the neighborhood of the dissolved coarse coordinates. The velocity variables are updated by a momentum conserving scheme. The properties of the stochastic updates are derived through the ChapmanKolmogorov and FokkerPlanck equations for the evolution of the probability distribution of coarsegrained position and velocity variables, by requiring the equilibrium distribution to be a stationary solution. We test our new scheme on concentrated star polymer solutions and find that the transverse current and velocity time autocorrelation functions behave as expected from hydrodynamics. In particular, the velocity autocorrelation functions display a long time tail in complete agreement with hydrodynamics.},
doi = {10.1063/1.4904315},
journal = {Journal of Chemical Physics},
number = 24,
volume = 141,
place = {United States},
year = 2014,
month =
}

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