Structure Generation and Seepage Performance Analysis of Porous Oil Containing Media with Variable Porosity Gradient Distribution

This approach enabled the generation of porous architectures with porosity varying along the height direction, including linear gradient structures (positive and negative gradients) and parabolic gradient structures (convex and concave types).

The lattice Boltzmann method (LBM) was employed to analyze the seepage behavior of lubricating oil within the porous medium. The results demonstrate that, under identical porosity conditions, the heterogeneity of pore distribution exerts a pronounced effect on fluid transport. Specifically, the average seepage velocities in both positive and negative linear gradient structures were lower than those in homogeneous porous structures, while the velocity in the negative gradient configuration was significantly higher than in its positive counterpart.