Abstract In the present work, a suite of numerical experiments with linear stability analysis are conducted to study density-driven flow with chemical dissolution of two reactive fluids in synthetic porous media. Linear stability analysis at the Darcy scale is first performed to predict the interfacial phenomena and instability at the initial time. Pore-scale simulations using the lattice Boltzmann method (LBM) are further conducted to capture more mechanistic information and advance the understanding of the transport processes. Under different scenarios, it is demonstrated that the transport processes exhibit distinct behaviors, which are largely dominated by the interplay among density contrast, chemical reaction rate and evolution of the porosity/permeability. All the results indicate that the interfacial instability can be triggered by the density contrast between two miscible fluids, leading to the Rayleigh-Taylor (R-T) instability. The R-T instability can be suppressed by the heterogeneous surface reaction between the fluid and solid phases, which prevents the transport of the denser fluid. Over the long term, it is found that the interfacial instability is influenced by the evolution of the porosity/permeability due to dissolution, which potentially restarts the transport of the denser fluid.

中文翻译：

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在多孔介质中溶解的密度驱动流动的多尺度研究

摘要 在目前的工作中，进行了一系列线性稳定性分析的数值实验，以研究合成多孔介质中两种反应流体化学溶解的密度驱动流动。首先进行达西尺度的线性稳定性分析，以预测初始时间的界面现象和不稳定性。进一步使用格子玻尔兹曼方法 (LBM) 进行孔隙尺度模拟，以捕获更多机械信息并促进对输运过程的理解。在不同的情景下，证明了输运过程表现出不同的行为，这在很大程度上取决于密度对比、化学反应速率和孔隙度/渗透率演变之间的相互作用。所有结果表明，界面不稳定性可以由两种混溶流体之间的密度对比触发，导致瑞利-泰勒 (RT) 不稳定性。RT 不稳定性可以通过流体和固相之间的异质表面反应来抑制，这会阻止密度较大的流体的传输。从长远来看，发现界面不稳定性受到由于溶解引起的孔隙率/渗透率演变的影响，这可能会重新启动密度较大的流体的传输。