Numerical investigation of PCM solidification in a finned rectangular heat exchanger including natural convection

The thermal energy storage got a significant role in the solar energy conservation to expand its use over time. To exploit solar energy continuously, we require a storage energy system. Phase Change Material (PCM) used in this kind of systems in order to store a great amount of thermal energy. This work concerns the solidification in the presence of the natural convection of a rectangular phase change material exposed to a cold airflow along the conducting sidewalls. With this intention, the first stage includes the presentation of a numerical model based on the conservation equations, treated by finite volume method. This numerical approach aims to follow the evolution of the various parameters characterizing the phenomenon of phase change (liquid-solid interface and solid fraction) during all the processes of solidification as well as the temperature and the velocity distribution in the PCM storage systems. Moreover, this study presents the transient evolution of the longitudinal air temperature profiles. It also presents the effect of fins number on heat transfer enhancement and the temporal evolution of the solidification front. The advantage of this study is to find a solution to extract the maximum of heat during the solidification of the PCM. This solution is to take into account the natural convection and also the addition of the fins. (C) 2018 Elsevier Ltd. All rights reserved.