Kinetic theory for dissipative particle dynamics: The importance of collisions

Kinetic theory of dissipative particle dynamics is developed in terms of a Boltzmann pair collision theory. The kinetic transport coefficients are com puted from explicit collision integrals and compared favourably with detail ed simulations. Previous theory is found to correspond to a weak scattering limit, or Vlasov theory, and previously reported discrepancies with simula tions are thereby largely resolved. In the large dissipation limit, we find that qualitatively new scaling behaviour for the transport coefficients is indicated.