在孔隙尺度上对孔隙介质中双域质量转移的评估
Leland Dorchester, Frederick D Day-Lewis1,2, Kamini Singha3
1Pacific Northwest National Laboratory, Earth Systems Science Division, 902 Battelle Boulevard, Richland, WA, 99352.
Ground water
|May 31, 2023
概括
溶液运输的双孔性模型是复杂的. 我们的毛孔尺度模拟显示,流速影响不动毛孔发育,挑战双域质量转移模型中的假设.
科学领域:
- 地质科学 地质科学
- 水文学 水文学
- 孔尺度物理学的物理
背景情况:
- 双孔度模型是异质介质中溶液运输的标准.
- 关键参数,如不运动的多孔性,很难通过实验来确定.
- 将模型参数与可测量的数量联系起来仍然是一个重大挑战.
研究的目的:
- 为了研究孔隙尺度流动动力学和不移的孔隙性发展之间的关系.
- 将双域质量转移 (DDMT) 模型中的有效长度尺度与几何流域特征进行比较.
- 评估流速如何影响孔尺度系统中的溶解物运输参数.
主要方法:
- 进行了合成,孔尺度的毫流体模拟.
- 结合模拟流体流动,溶液运输和电阻力 (ER).
- 在两个模型场景 (内部孔隙和内部孔隙) 中,在四个不同的流速下进行模拟导电跟踪测试.
主要成果:
- 即使在明确单域系统中,移动和不移动域也出现了.
- 较高的流速与不移到移动的多孔度比率和质量转移率的增加相关.
- 计算Peclet数 (LPe) 的长度尺度始终大于质量转移率 (Lα) 的长度尺度.
结论:
- 估计不移的孔隙性受流速和流障碍的影响,而不仅仅是物理孔隙空间.
- 由于流动动力学,双域质量转移模型可能会高估不移的孔隙性.
- 孔尺度模拟提供了对传统双孔度模型的局限性的洞察.
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