Simulation of liquid flow transport in nanoscale porous media using lattice Boltzmann method

Abstract

Clarifying the confined liquid flow in nanoscale porous media is crucial for many science and engineering applications, such as shale/tight oil recovery. However, most of the investigations are focused on the single pore and the uniform wet, and there are few effective nanoscale pore-scale simulation methods. In this paper, we comprehensively study the confined water flow in shale porous media from the theoretical analysis to a new nanoscale lattice Boltzmann method (LBM). The nanoscale effects of the slip boundary and the varying interfacial water viscosity caused by the solid-liquid molecular interactions are considered. Additionally, the water flowing in shale porous media coupling different transport mechanisms in the water-wetting inorganic and oil-wetting organic media is simulated and discussed. The results show that the water flow behaviors obtained by (LB) simulations fit well with that calculated by the theoretical analysis. Then, the controllable nanoscale effects are successfully brought into LB simulation. Additionally, the nanoscale effects of the slip boundary and the interfacial fluid viscosity have a great impact on the water flow capacity, and the confined water flow behaviors are sensitive to heterogeneous wettability and pore size.