DPD simulation of multiphase flow at small scales

Small scale multiphase fluid motion is fundamentally important for applications in environmental, biological and chemical engineering as well as many other areas. Due to the existence of complex geometries, arbitrarily moving interfaces, and large density and viscosity contrast, simulation of small scale multiphase flows has been a formidable task for traditional grid-based numerical methods. This paper presents the application of a meso-scale, Lagrangian particle method, dissipative particle dynamics (DPD), for simulating multiphase fluid flows. For multiple component multiphase flows, with properly selected coefficients, the conventional DPD model can be directly used. For single component multiphase flows, the conservative weight function describing DPD particle-particle interactions has to be modified to model the existing liquid-gas phases. The effectiveness of the DPD model in simulating multiphase flows has been demonstrated by two numerical examples of two-component two phase flow, and one-component two phase flow.