ANFIS-based modeling of packed bed thermal energy storage with phase change material: A novel geometric design for enhanced performance

Packing Bed Thermal Energy System (PBTES) are employed for heating, drying, and recovering thermal energy due to their simplicity, efficiency, and cost-effectiveness. This study explores the potential of porous foam gradients and phase change materials (PCMs) as an innovative strategy to boost the thermal performance of PBTES. The investigation examines the impact of different PCMs—specifically RT-42, RT-38, and RT-35HC—along with varying flow rates, Darcy numbers, and porosities. For the numerical analysis, ANSYS Fluent software was employed in two scenarios: one involving a complete concrete sample and the other featuring concrete mixed with PCM in various geometries. The findings disclose that the ratio of energy released to energy gathered ( and the energy efficiency of the full concrete scenario peak at the highest air mass flow rate. For RT42, the greatest temperature increase is observed at a porosity of 0.55, while the mean temperature of the PCM shows the most significant rise in maximum temperature at a porosity of 0.75. The improved across all Darcy numbers compared to the porous medium, with the highest energy efficiency noted at a Darcy number of 1e-09. In the second scenario, when analyzing different PCMs, RT42 achieved the highest maximum temperature in the system, while RT35HC had the lowest. Applying ANFIS modeling, the was accurately predicted, achieving a correlation coefficient of 0.92.