Lees–Edwards boundary condition for simulation of polymer suspension with dissipative particle dynamics method

Abstract

The Lees–Edwards boundary condition (LEbc) is widely used in particle-based simulation for producing shear flow. Application of traditional LEbc in dissipative particle dynamics (DPD) method may encounter certain problems, e.g. it will destroy the momentum conservation law at the near boundary region, and the coordinate system gives an incorrect end-to-end vector for polymer beads. Special treatments of the implementation of LEbc in DPD method are introduced in this paper. A single side ghost layer is used to keep the momentum conservation, and the global coordinate system is employed to obtain a correct calculation of the spring force between polymer beads. The simulation results give a good prediction of velocity profile and system temperature, and the elastic dumbbell model for current method can well represent the Oldroyd-B fluid.