在表面水-地下水界面的高度短暂的流量场下,多孔介质中的羽毛层几何,稀释和反应混合的演变
Mónica Basilio Hazas1, Francesca Ziliotto1, Jonghyun Lee2
1Chair of Hydrology and River Basin Management, Technical University of Munich, Munich, Germany.
Journal of contaminant hydrology
|September 11, 2023
概括
过渡的边界条件,如水,增强地下水中的溶液混合. 这项研究表明,波动的地表水增加了羽毛稀释和反应速率,特别是在低地下水流速时.
科学领域:
- 环境科学 环境科学
- 水文地质学 水文地质学
- 地质化学 地质化学
背景情况:
- 表面水与地下水的相互作用对于溶液运输至关重要.
- 水力发电运营会导致水上冲破,从而产生暂时的边界条件.
- 了解这些过渡物对于管理地下水质量至关重要.
研究的目的:
- 研究表面水的波动对水层中溶液运输的影响.
- 在稳定和短暂的流动下量化羽毛稀释,面积和周长.
- 分析反应混合和反应控制的过程.
主要方法:
- 实验室流通实验与保守的标记剂注射.
- 用于度测量的光学成像.
- 使用非线性,取决于速度的分散式运输模型进行数值模拟.
主要成果:
- 过渡条件显著增加了羽毛积,周围和稀释.
- 低地下水流速显示混合的相对增强更大.
- 在羽毛面积演变和稀释指数之间发现了线性关系.
- 短暂的流动增强了反应混合,导致污染物的降解速度更快.
结论:
- 极度短暂的边界条件改善了地下水中的溶液混合和污染物降解.
- 类似于水上的场景表明混合和反应的增强,特别是在较慢的地下水系统中.
- 过渡性流提供了一种机制,可以在地表水-地下水界面加速地表水污染的修复.
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