Two-dimensional anisotropy, heterogeneity and different pore shape of micro-porous media were generated by adopting the quartet structure generation set (QSGS) method, randomly distributed particles method and random fracture generation method, while the improved QSGS method was utilized to generate two-dimensional fracture-pore dual media. By applying bounce-back wall boundary condition, a multi-relaxation-time lattice Boltzmann (MRT-LB) model was adopted to simulate fluid flow in porous media for analyzing the correlation of tortuosity with pore structure in micro-porous media. The simulation results show that porosity, anisotropy, heterogeneity, pore shape and fracture all affect tortuosity, while porosity, anisotropy, pore shapeand fracture play a more significant role. The tortuosity of the circular pore media is generally greater than that of the fractured porous media, while the tortuosity of the intergranular pore media is basically in the middle. The aperture and strike of fracture significantly affect the tortuosity of fracture-pore dual media. Meanwhile, the existing tortuosity models are not suitable for complex porous media. Finally, the relations of tortuosity with anisotropy and porosity are established respectively based on the simulation results.This workis helpful to further reveal the relationshipbetweentortuosity and pore structurein micro-porous media.
Li Tao, Li Min, Zhang Lie-hui, Tian Shan-chuan, Zhao Xiao-yu, Zheng Ling-li
. Study on the relationship of tortuosity with pore structure in micro-porous media[J]. Natural Gas Geoscience, 2018
, 29(8)
: 1181
-1189
.
DOI: 10.11764/j.issn.1672-1926.2018.06.013
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