TY - EJOU AU - Feng, Min AU - Wang, Long AU - Sun, Lei AU - Yang, Bo AU - Wang, Wei AU - Luo, Jianning AU - Wang, Yan AU - Liu, Ping TI - Characterization of Pore Structure and Simulation of Pore-Scale Flow in Tight Sandstone Reservoirs T2 - Fluid Dynamics \& Materials Processing PY - 2025 VL - 21 IS - 3 SN - 1555-2578 AB - This study sheds light on how pore structure characteristics and varying dynamic pressure conditions influence the permeability of tight sandstone reservoirs, with a particular focus on the Paleozoic reservoirs in the Qingshimao Gas Field. Using CT scans of natural core samples, a three-dimensional digital core was constructed. The maximum ball method was applied to extract a related pore network model, and the pore structure characteristics of the core samples, such as pore radius, throat radius, pore volume, and coordination number, were quantitatively evaluated. The analysis revealed a normally distributed pore radius, suggesting a high degree of reservoir homogeneity and favorable conditions for a connected pore system. However, it was found that the majority of throat radii measured less than 1 μm, which severely restricted fluid flow and diminished permeability. Over 50% of the pores measured under 100 μm3, further constraining fluid movement. Additionally, 30%–50% of the pore network was composed of isolated and blind-end pores, which significantly impaired formation connectivity and reduced permeability. Based on this, the lattice Boltzmann method (LBM) was used for pore-scale flow simulation to investigate the influence mechanism of pore structure characteristics and dynamic-static parameters such as displacement pressure difference on the permeability performance of the considered tight sandstone reservoirs for various pressure gradients (0.1, 1, and 10 MPa). The simulations revealed a strong relationship between pressure differential and both the number of streamlines and flow path tortuosity. When the pressure differential increased to 1 MPa, 30 streamlines were observed, with a tortuosity factor of 1.5, indicating the opening of additional seepage channels and the creation of increasingly winding flow paths. KW - Tight sandstone; digital core; flow simulation; lattice Boltzmann method DO - 10.32604/fdmp.2024.056421