A Numerical Investigation of Oscillating Flow and Condensation in Porous Structures Using the Lattice Boltzmann Method

Oscillating multiphase flow and heat transfer in porous media are crucial in diverse energy systems, including pulsating heat pipes, thermal energy storage, and enhanced geothermal systems. However, a fundamental understanding of the governing mechanisms remains unclear. Specifically, the interaction between oscillation dynamics and multiphase heat transfer within complex porous structures is poorly defined due to the intricate porous structure. Furthermore, the coupling between oscillation dynamics and multiphase heat transfer within the complex architecture of porous media is not well characterized. Meanwhile, the influence of surface wettability of porous structures on phase change dynamics and flow behavior has yet to be fully elucidated.

To address these knowledge gaps, this study employs Lattice Boltzmann Method (LBM) simulations, a computational approach exceptionally well-suited for resolving mesoscopic scale physics within complex boundaries. Computational domains are digitally reconstructed from high-resolution micro-computed tomography (micro-CT) scans of natural coral rock, a material chosen for its inherently complex structure formed within an environment of natural oscillations. The primary objective is to systematically investigate how key oscillation parameters (e.g., frequency, amplitude) and variations in surface wettability affect condensation processes in porous structures, including condensation formation, and overall heat transfer efficiency.