Solute transport in partially-saturated porous media plays a key role in multiple applications across scales, from the migration of nutrients and contaminants in soils to geological energy storage and recovery. Our understanding of transport in unsaturated porous media remains limited compared to the well-studied saturated case. The focus of this review is the non-reactive transport driven by the displacement of immiscible fluids, where the fluid-fluid interface acts as a barrier that limits the solute to a single fluid phase. State-of-the-art pore-scale models are described, with a critical analysis of the gaps and challenges. A numerical example is provided to demonstrate the acute sensitivity of solute transport prediction to minute, inevitable uncertainties in the spatial distribution of the fluids' velocities and interface configuration associated with the multiphase flow modeling.

中文翻译：

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部分饱和多孔介质中溶质输运的孔隙尺度模拟


部分饱和多孔介质中的溶质传输在跨尺度的多种应用中发挥着关键作用，从土壤中养分和污染物的迁移到地质能量储存和恢复。与经过充分研究的饱和情况相比，我们对不饱和多孔介质中传输的理解仍然有限。本综述的重点是由不混溶流体的位移驱动的非反应性输运，其中流体-流体界面充当将溶质限制为单一流体相的屏障。描述了最先进的孔隙尺度模型，并对差距和挑战进行了批判性分析。提供了一个数值示例来证明溶质输运预测对与多相流建模相关的流体速度和界面配置的空间分布中不可避免的微小不确定性的敏锐敏感性。