Non-ideal DPD fluids

We propose a new method for implementing conservative forces in a dissipative particle dynamics (DPD) system. We allow multibody interactions, and use information on the macroscopic equilibrium behaviour of the system. We show that it is then possible to induce a fluid/fluid phase transition, and also that the local structure is then less pronounced than in previous models. This last feature is desirable in the description of fluids at a mesoscopic scale.