A systematic method for the complex walls no-slip boundary condition modeling in dissipative particle dynamics

The dissipative particle dynamics method is an efficient method for studying the hydrodynamics of complex fluids. One of the most challenging aspects of this method appears when the solid walls exist. The solid walls disturb the homogeneity of the fluid near the wall and cause some spurious fluctuations. Thus, in recent years a large amount of effort has been devoted to solve this shortcoming. Fortunately the mentioned problem has almost been solved for the simple walls such as flat walls, circular cylinders, spheres, etc. However no systematic model has addressed the complex walls. It should be noted that almost all of the walls we deal with in practical problems such as MEMS devices, polymer and drug containers and so on have complex geometries.In the present paper, we present a systematic method for the dissipative particle dynamics simulation of complex walls based on the representation of the complex wall by means of a triangular grid. We demonstrate the validity of our model for the flow past over a circular cylinder and then we do a simulation for the flow over an airfoil. The obtained results show that this method facilitates the simulation of each arbitrary complex wall while the spurious fluctuations of density and temperature are diminished effectively near the wall.