INSIDE THE PCM MELTING EVOLUTION: A CFD INVESTIGATION OF METAL PERIODIC STRUCTURES TO ENHANCE THERMAL DIFFUSION

Phase change materials (PCMs) play a pivotal role in thermal energy storage systems, as they can efficiently store and release energy during phase transitions. Enhancing the melting process of PCMs is crucial for improving the overall performance of these systems. This study presents a computational fluid dynamics (CFD) analysis of periodic structures designed to enhance PCM melting in an insulated cubic domain subject to a Dirichlet boundary condition on one side. The influence of various periodic structures like the cubic and octahedral on the melting behaviour of PCMs is investigated. Moreover, numerical simulations consider a range of materials, i.e., copper, steel, and aluminium, integrated into the PCM cubic domain. The pore-scale analysis focuses on key parameters, including melting time, temperature distribution, and energy stored. Results of this study confirm that the choice of periodic structure significantly impacts the melting performance of PCMs as the octahedral grid increases the average fraction of melted PCM over time. Through CFD simulations, we identify benefits of changing structures to enhance heat transfer and consequences of varying porosity on energy storage. Moreover, we provide insights into the influence of factors such as material properties and operating conditions on the melting process. These insights can be useful to enhance the efficiency and sustainability of energy storage technologies.