title: Comparison of lattice-Boltzmann and brownian-dynamics simulations of polymer migration in confined flows.
abstract: This paper compares results from lattice-Boltzmann and brownian-dynamics simulations of polymer migration in confined flows bounded by planar walls. We have considered both a uniform shear rate and a constant pressure gradient. Lattice-Boltzmann simulations of the center-of-mass distribution agree quantitatively with brownian-dynamics results, contradicting previously published results. The mean end-to-end distance of the extended polymer is more sensitive to grid resolution Δx and time-step Δt. Nevertheless, for sufficiently small Δx and Δt, convergent results for the polymer stretch are obtained which agree with brownian dynamics within statistical uncertainties. The brownian-dynamics simulations incorporate a mobility matrix for a confined polymer that is both symmetric and positive definite for all physically accessible configurations.
authors.affiliation: Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611-6005, USA.
authors.forename: Rahul
authors.initials: R
authors.lastname: Kekre
authors.forename: Jason E
authors.initials: JE
authors.lastname: Butler
authors.forename: Anthony J C
authors.initials: AJ
authors.lastname: Ladd