Representative pore-scale geometric modeling and simulation methodologies of flow and heat transfer in porous media: a review

Porous media find widespread use in chemical reaction beds, high-efficiency heat transfer devices, thermal protection engineering for aerospace hot-end components and thermoelectric conversion systems owing to their permeable properties and high heat transfer capacity. Pore-scale simulations, which can reveal detailed flow and heat transfer processes within pore channels, play a crucial role in the investigation of the sources of flow resistance and the mechanisms of heat transfer. This paper first reviews geometric modeling methods for porous media. For materials fabricated by conventional processing, modeling can be conducted using either simplified approaches or reconstruction based on imaging techniques. In addition, additive manufacturing enables the realization of intended structures, providing support for porous media design, and is therefore also discussed. Secondly, this paper discusses pore-scale numerical simulation methods, including the pore network model (PNM) that simplifies pore structures into macropores and throats, the conventional CFD method for solving the Navier–Stokes (NS) equations, the lattice Boltzmann method (LBM) based on mesoscopic kinetic theory and the use of neural networks to predict flow and heat transfer. The characteristics of each method are compared and recommendations for their application are provided. Finally, prospects for the modeling and simulation methods of flow and heat transfer within porous media at the pore scale are discussed, including high-fidelity CT imaging and pore-structure reconstruction, multi-method coupling and hybrid simulation, and rapid pore-scale predictive models. In general, this paper summarizes geometric modeling methods for porous media with different morphologies and compares the differences between various numerical simulation schemes. This review can guide future investigations involving pore-scale numerical simulations of flow and heat transfer in porous media.