Coupled Flow and Deformation Dynamics in Swelling and Shrinking Porous Media: Mechanisms, Modeling, and Applications

Swelling and shrinking behaviors in porous media are critical to understanding a variety of static and dynamic processes, influencing the geomechanical behavior of the reservoir rock. The objective of this study is to investigate the coupling between fluid flow and deformation in porous materials, particularly focusing on the mechanical and transport properties, size and shape changes of the pores, and the formation of induced fractures. Integrates advanced experimental techniques, theoretical modeling, and visualization tools to uncover the mechanics of swelling and shrinking were used to characterize the changes in the porous media. Experiments were conducted using imaging methods such as micro-computed tomography (μCT) to capture deformation patterns and changes in porosity and permeability. Coupled flow-deformation models were developed based on poroelastic theories, incorporating numerical formulations for fluid flow, stress distribution, and strain evolution. Numerical simulations using finite element methods (FEM) were employed to predict deformation and fracture behavior under varying swelling or shrinking regimes. The results show intricate couplings between flow, deformation, and material failure in porous systems. For shaly swelling materials, fluid influx induces localized stress concentrations that lead to fracture formation or surface wrinkling, depending on material physical and mechanical properties and boundary conditions. In contrast, shrinking systems exhibit volume reduction and compaction-driven changes in permeability and porosity. These behaviors are strongly influenced by the mechanical heterogeneity of the formation and the rate of fluid transport. Additionally, visualization tools highlighted the evolution of microstructural changes during swelling and shrinking, offering unprecedented insights into the underlying mechanisms. In conclusion, this study provides an integrated framework for analyzing the coupling of flow and deformation in swelling and shrinking porous media. The innovation lies in the integration of experimental observations with theoretical and numerical models, enabling accurate predictions of behavior under varying conditions. This work significantly advances our understanding of deformation mechanics in porous systems, contributing to the optimization of processes such as fracture design in geomechanics, controlled swelling in shaly formation. Future research will focus on extending the models to account for multi-physics phenomena, such as mechanical, chemical reactions and temperature changes, to enhance the applicability in complex deformation environments.