页岩微纳米尺度孔隙气体流动的影响因素分析

he existence of nano-pores in shale has been revealed recently by Scanning Electron Microscope (SEM). The developed nano-pores could result in complicated non-Darcy effects, so the classical gas flow simulation approaches based on Darcy's law may not be appropriate for simulating shale gas flow in shale. Based on the Lattice Boltzmann Method (LBM) with non-ideal gas state equation, considering the influences of gas slippage, absorption effect and Knudsen layer, a nano-channels model was established to study the influences of pore size, pressure and temperature on microscale flow in shale reservoirs. The simulation results show that these parameters have a significant impact to the gas flow in nano-channels of organic matter by affecting the compressibility effect and slippage effect. In particular, the absorption effect is sensitive to pressure or temperature. Therefore, we comprehensively investigated the microcosmic gas flow mechanism and its influencing factors in shale, which not only have important theoretical value in understanding the shale gas transport mechanism in a kerogen pore, but also have practical guidance for optimal development strategy.