Impact of phase change materials types and positioning on hot water tank thermal performance: Using measured water demand profile

This paper addresses a numerical investigation of the performance of a domestic hot water tank (HWT) integrated with phase change materials (PCM). The predictions made by three TRNSYS types were compared and the most appropriate one was selected as reference model. Then, the existing TRNSYS model for HWT with PCM was validated with the available data. The validated model was then used to investigate the impact of PCM type, its amount and its location within the tank on the system performance using the three real hot water withdrawal profiles; low, medium and high. An improvement in energy storage resulted from the combined use of PCM and sensible heat in a HWT with sodium acetate trihydrate +10% graphite showing the highest storage potential with reduce charging time compared to an industrial grade granulated paraffin wax and RT58-Rubitherm.