Large scale and mesoscopic hydrodynamics for dissipative particle dynamics

Decay rates and related transport coefficients of hydrodynamic disturbances in the isothermal dissipative particle dynamics (DPD) fluid depend strongl y on how the probing wave length (in simulations: sizes of colloidal partic les, polymers, pores, etc.) compares to the dynamic correlation length and to the range of the DPD forces. In this article the wave number dependent t ransport properties (dispersion relations) of the DPD fluid are calculated analytically using methods of kinetic theory, as a natural generalization o f the work by Marsh [Phys. Rev. E 56, 1976 (1997)]. The Navier-Stokes trans port coefficients are recovered in the hydrodynamic limit of long wavelengt h disturbances. (C) 2001 American Institute of Physics.