The drying phenomenon in soils involves complex interactions between thermal, hydrological, and mechanical effects within a multiphase system. While several researches (both mechanics and mixture theory approach) has been applied to study various thermo-hydro-mechanical (THM) coupled processes in porous media, incorporating both multiphase flow and phase change in soil drying remains limited. This work addresses this research gap by deriving new governing equations for a two-phase flow model suitable for soil drying by extending the mixture coupling approach. The derived model is implemented in COMSOL Multiphysics and validated against experimental data, demonstrating good agreement between the model predictions and the ob- served results. A sensitivity analysis is performed to investigate the impact of critical parameters on the drying process. The findings reveal that volumetric strain is most sensitive to Young’s modulus, while the saturation of liquid water is most affected by intrinsic permeability. Additionally, preliminary results for a kaolinite clay sample during the drying process are presented, extending the applicability of the derived model to specific soil types. This research provides a comprehensive framework for fully THM coupled modelling of soil drying, which can serve as a basis for future investigations.

中文翻译：

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基于混合耦合理论的相交换多相热-水-力耦合土壤干燥模型


土壤干燥现象涉及多相系统内热、水文和机械效应之间的复杂相互作用。虽然一些研究（力学和混合理论方法）已应用于研究多孔介质中的各种热-水-机械（THM）耦合过程，但在土壤干燥中结合多相流和相变仍然有限。这项工作通过扩展混合物耦合方法，推导适用于土壤干燥的两相流模型的新控制方程，弥补了这一研究空白。导出的模型在 COMSOL Multiphysics 中实现，并根据实验数据进行验证，证明模型预测与观测结果之间具有良好的一致性。进行敏感性分析以研究关键参数对干燥过程的影响。研究结果表明，体积应变对杨氏模量最敏感，而液态水的饱和度受固有渗透率的影响最大。此外，还给出了高岭石粘土样品在干燥过程中的初步结果，将推导模型的适用性扩展到特定土壤类​​型。这项研究为土壤干燥的全 THM 耦合建模提供了一个全面的框架，可以作为未来研究的基础。