Flow simulations with multi-particle collision dynamics

Abstract

Multi-particle collision dynamics (MPCD) is a particle based Navier-Stokes solver and in the last ten years it has been largely used to analyze mesoscopic systems where both hydrodynamics and thermal effects have to be taken into account, typical examples being colloidal suspensions and polymer solutions. Though the soundness of this approach is well documented, only a few studies present a systematic validation of the method as a Navier-Stokes solver for relatively complex flows (e.g. unsteady, non-uniform). In this study we use MPCD to simulate an unsteady periodic flow (second Stokes’ problem) and a two dimensional flow (lid-driven cavity). Quantitative comparisons with analytical and finite difference results show that MPCD is able to correctly reproduce the hydrodynamics of these systems in a wide range of numerical parameter values, allowing the applications of MPCD to the analysis of complex fluids in confined geometries such as in Lab-On-a-Chip microfluidic devices. Discrepancies for certain parameter ranges and in specific flow conditions are singled out and discussed.