Performance characterisation of thermal energy storage containing a Phase Change Material (PCM) sphere with low conductivity fins: simulation-based analysis

This paper presents the outcomes of a simulation study aimed at investigating the thermal performance of modified phase change material (PCM) structures within a sphere with integrated fins. The escalating global warming crisis and its associated weather anomalies necessitate urgent measures to mitigate its impacts. Numerous research endeavours have been undertaken to address this issue, including the utilization of thermal energy storage systems (TES) augmented with PCM. PCM can be incorporated into building walls to counteract rising temperatures. However, inadequate heat transfer caused by poor thermal conductivity has been a persistent challenge in these systems. The addition of high conductivity fins has found to improve the overall performance of TES. Yet, this study proposes the addition of low conductivity fins to study for the effect of shape factor to its performance. The research evaluates the phase change of 2-fins and 4-fins with varying thicknesses within the PCM structure. A comprehensive simulation framework is employed to analyse the thermal behaviour of the PCM-enhanced sphere without considering ambient temperature nor PCM properties, but fin dimensions and configurations. The simulation results reveal that the inclusion of fins significantly improves heat transfer within the system by cutting a minimum of 20% in phase change time and could promote the phase change process to happen earlier by a maximum of 38% in starting time. By optimizing the fin configuration and thickness, the overall thermal conductivity of the PCM-based TES can be enhanced. These findings contribute to the development of efficient thermal energy storage systems, offering potential solutions to combat global warming and promote sustainable thermal management.