Mesoscopic simulations of the counterion-induced electroosmotic flow - a comparative study

TL;DR

This paper compares mesoscopic simulation methods for electroosmotic flow induced by counterions across different electrostatic regimes, developing a mapping scheme and analyzing effects like electrofriction and slip conditions.

Contribution

It introduces a mapping scheme to align DPD and LB/MD simulations and compares their effectiveness in modeling electroosmotic flow across regimes.

Findings

Good agreement between analytic and numerical flow profiles in weak-coupling regime

Electrofriction significantly influences flow behavior

Partial slip boundary conditions alter flow profiles

Abstract

We present mesoscopic simulations of the counterion-induced electroosmotic flow in different electrostatic coupling regimes. Two simulation methods are compared, Dissipative Particle Dynamics (DPD) and coupled Lattice-Boltzmann/Molecular Dynamics (LB/MD). A general mapping scheme to match DPD to LB/MD is developed. For the weak-coupling regime, analytic expressions for the flow profiles in the presence of partial-slip as well as no-slip boundary conditions are derived from the Poisson-Boltzmann and Stokes equations, which are in good agreement with the numerical results. The influence of electrofriction and partial slip on the flow profiles is discussed.