STATIC AND DYNAMIC PROPERTIES OF DISSIPATIVE PARTICLE DYNAMICS

The algorithm for the dissipative particle dynamics (DPD fluid, the dy namics of which is conceptually a combination of molecular dynamics, B rownian dynamics, and lattice gas automata, is designed for simulating rheological properties of complex fluids on hydrodynamic: time scales . This paper calculates the equilibrium and transport properties (visc osity, self-diffusion) of the thermostated DPD fluid explicitly in ter ms of the system parameters. It is demonstrated that temperature gradi ents cannot exist, and that there is therefore no heat conductivity. S tarting from the N-particle Fokker-Planck, or Kramers equation, He pro ve an H theorem for the free energy, obtain hydrodynamic equations. an d derive a nonlinear kinetic equation the Fokker-Planck-Boltzmann equa tion) for the single-particle distribution function. This kinetic equa tion is solved by the Chapman-Enskog method. The analytic results are compared with numerical simulations.