Investigation the Influence of Phase Change Material Amount on a Hot-Water Stratification in Charging Mode

Among the various techniques for enhancing the storage and consumption of energy in a thermal energy storage system, the establishment of thermal stratification in a hot-water container is an effective technology. The current study aims to assess the performance of the thermal stratification for hot-water containers using (ANSYS Fluent) R.1.0, 2022, through the study of the impact of different numbers of paraffin-filled containers, namely 3, 5, and 7, that are equivalent to 5, 7, and 9 kg of paraffin, respectively. To validate the present numerical model, a comparison between the current study results and the experimental findings from the literature was conducted, and the results demonstrated that there was a good approval between these results. The results of this study depict that the profile temperature at the outlet of the container indicates an enhancement in the Richardson number and stratification number by 37.9% and 45.8%, respectively, when the charging process is finished. Furthermore, increasing the number of paraffin-filled containers from 5 to 9 results in a 29.9% improvement in charging efficiency, resulting in an improvement in storage efficiency. Finally, the results have proven that the 3D CFD approach is a highly beneficial tool to assess the effect of PCM mass on stratification performance in a hot-water container.