In this study, in order to investigate the effect of the underlying pore-scale processes on continuum scale simulations of porous media dissolution, we improve the standard Lattice Boltzmann method using Quadtree grid refinement approach to simulate fluid flow and reactive transport through large domain sizes. Our results have shown considerable computational improvements up to 80% in simulation time together with increased numerical accuracy. The results and the added value of the new approach are discussed using comparison of our model with the conventional LBM. Moreover, we have applied a systematic analysis by increasing complexity levels and starting from fluid flow and continuing with tracer transport and reactive transport in single pores, and ultimately, reactive transport in dissolving porous structures. For each case, the accuracy and computational benefits of the Quadtree models are discussed and dimensionless numbers are used to characterize regimes of flow and reaction in each step of comparison. Porosity-permeability variation in a 2D pore structure and mass transfer coefficient in a closed-end fracture with porous walls are then evaluated under different flow conditions.

在这项研究中，为了研究潜在的孔隙尺度过程对多孔介质溶解的连续尺度模拟的影响，我们改进了标准的格子玻尔兹曼方法，使用四叉树网格细化方法来模拟流体流动和通过大域尺寸的反应传输。我们的结果表明，模拟时间的计算改进高达 80%，同时数值精度也提高了。通过将我们的模型与传统 LBM 进行比较，讨论了新方法的结果和附加值。此外，我们通过提高复杂性水平并从流体流动开始，继续进行单孔中的示踪剂传输和反应性传输，并最终在溶解中进行反应性传输，从而应用了系统分析。多孔结构。对于每种情况，都讨论了四叉树模型的准确性和计算优势，并使用无量纲数来表征每个比较步骤中的流动和反应状态。然后在不同的流动条件下评估二维孔隙结构中的孔隙率-渗透率变化和具有多孔壁的封闭端裂缝中的传质系数。