TY  - JOUR
AU  - Ripoll, M.
AU  - Mussawisade, K.
AU  - Winkler, R. G.
AU  - Gompper, G.
TI  - Dynamic Regimes of Fluids Simulated by Multi-Particle-Collision Dynamics
JO  - Physical review / E
VL  - 72
IS  - 1
SN  - 1539-3755
CY  - College Park, Md.
PB  - APS
M1  - PreJuSER-47063
SP  - 016701
PY  - 2005
N1  - Record converted from VDB: 12.11.2012
AB  - We investigate the hydrodynamic properties of a fluid simulated with a mesoscopic solvent model. Two distinct regimes are identified, the "particle regime" in which the dynamics is gaslike and the "collective regime" where the dynamics is fluidlike. This behavior can be characterized by the Schmidt number, which measures the ratio between viscous and diffusive transport. Analytical expressions for the tracer diffusion coefficient, which have been derived on the basis of a molecular-chaos assumption, are found to describe the simulation data very well in the particle regime, but important deviations are found in the collective regime. These deviations are due to hydrodynamic correlations. The model is then extended in order to investigate self-diffusion in colloidal dispersions. We study first the transport properties of heavy pointlike particles in the mesoscopic solvent, as a function of their mass and number density. Second, we introduce excluded-volume interactions among the colloidal particles and determine the dependence of the diffusion coefficient on the colloidal volume fraction for different solvent mean-free paths. In the collective regime, the results are found to be in good agreement with previous theoretical predictions based on Stokes hydrodynamics and the Smoluchowski equation.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000230887100106
DO  - DOI:10.1103/PhysRevE.72.016701
UR  - https://juser.fz-juelich.de/record/47063
ER  -