A many-body dissipative particle dynamics simulation of flow performance in capillary channel

Fluid flow at the mesoscale has become an attractive topic of interest to improve the fluid transport behavior in reservoir formations. It is greatly advantageous to investigate the transport phenomena of small characteristic sizes by the many-body dissipative particle dynamics (MDPD) method. This work analyzes the wetting behavior between MDPD fluid particles and solid walls by tuning the attractive parameter, where an increase in attractive parameter value actually leads to weaker attraction in MDPD simulations. Parallel-plate flows for smooth and rough surfaces are used to investigate the transport property of MDPD fluid particles. The flow performance in capillary models is also studied. Results indicate that both surface and capillary contact angles increase with the rise of the attraction parameter. For smooth and rough walls, the velocity profiles show the parabolic shape. The velocities increase with increasing levels of attraction parameters and external forces. When the wettability of the solid wall decreases (or the attraction coefficient increases), the kinetic energy of MDPD fluid particles increases in comparison to the strongest wetting. The presence of a rough wall has a noticeable effect on the velocity distribution close to the wall, while the type of wall grooves has very little effect. Moreover, the different types of grooves do not affect the center velocity too much. The displacement particle number (the number of external particles entering the monitoring range) tends to rise with increasing external pressure and capillary diameter. Some conditions, such as low surface hydrophilicity, high external pressure, and large capillary diameter, can improve the flow performance. This MDPD simulation strategy provides a systematic study of flow transport behavior at the mesoscopic scale. It also can be readily extended to investigate more complex flow in formation conditions.