Interplay of viscosity and wettability controls fluid displacement in porous media
Interplay of viscosity and wettability controls fluid displacement in porous media
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DOI：
10.1103/physrevfluids.8.094002
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发表时间：
2023-04
影响因子：
2.7
通讯作者：
Saideep Pavuluri;R. Holtzman;Luqman Kazeem;Malyah Mohammed;T. Seers;H. Rabbani
中科院分区：
文献类型：
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作者：
Saideep Pavuluri;R. Holtzman;Luqman Kazeem;Malyah Mohammed;T. Seers;H. Rabbani
采用直接数值模拟的方法研究了非均质多孔介质中润湿性和流体粘度对非混相流体驱替的影响。基于定性和定量分析，我们将流动模式分为粘性指动（低M$）、紧凑位移（高M$）和中间过渡模式（M$ \约1$）。我们用稳定性分析得到了这些体系之间的理论相界，与我们的分析结果一致。在宏观（样品）尺度上，我们发现润湿性强烈地控制着阈值$M$（在该阈值处体系发生变化）。在孔隙尺度上，润湿性改变了主要的孔隙填充机制。在非常小的$M$（粘性指动状态）下，较小的孔隙空间在渗吸过程中被优先侵入，侵入流体膜沿着孔壁流动。相反，在排水过程中，无论孔隙大小如何，爆裂都会导致孔隙填充。随着$M$的增加，润湿性的影响减弱，无论润湿性如何，协同填充都成为主导机制。这表明，对于一定接触角下的吸胀，减小的$M$与有效润湿从中性湿（协同填充）到强湿（膜流）的变化有关。
Direct numerical simulations are used to elucidate the interplay of wettability and fluid viscosities on immiscible fluid displacements in a heterogeneous porous medium.We classify the flow regimes based using qualitative and quantitative analysis into viscous fingering (low $M$), compact displacement (high $M$), and an intermediate transition regime ($M \approx 1$). We use stability analysis to obtain theoretical phase boundaries between these regimes, which agree well with our analyses. At the macroscopic (sample) scale, we find that wettability strongly controls the threshold $M$ (at which the regimes change). At the pore scale, wettability alters the dominant pore-filling mechanism. At very small $M$ (viscous fingering regime), smaller pore spaces are preferentially invaded during imbibition, with flow of films of invading fluid along the pore walls. In contrast, during drainage, bursts result in filling of pores irrespective of their size. As $M$ increases, the effect of wettability decreases as cooperative filling becomes the dominant mechanism regardless of wettability. This suggest that for imbibition at a given contact angle, decreasing $M$ is associated with change in effective wetting from neutral-wet (cooperative filling) to strong-wet (film flow).