Thermal Performance Assessment of Domestic Hot Water Tanks with PCM and Energy Efficiency Improvement Through CFD Analyses
DOI:
https://doi.org/10.5281/zenodo.18362176Keywords:
phase change material, energy efficiency, domestic hot water, thermal energy storage, computational fluid dynamicsAbstract
Energy efficiency has become increasingly critical in domestic hot water tank (DHWT) systems, as DHWT use accounts for approximately 30% of total energy consumption in buildings. Phase Change Material (PCM) integrated systems offer significant potential for improving thermal performance compared to conventional water-based storage. In this study, the charging, discharging, and heat loss behaviour of PCM-integrated DHWT were evaluated using Computational Fluid Dynamics (CFD). The results showed that adding 3 kg of paraffin-based PCM to a 300 L DHWT increased the usable hot water volume by at least 10% without significantly affecting the charging time. While the conventional tank provided usable hot water for 14.10 minutes, PCM integration extended this time by approximately 2 minutes due to the latent heat released during solidification. A heat loss analysis conducted according to the TS EN 12897+A1:2020-03 standard revealed that the conventional system showed a heat loss of 86.9 W at 55 °C, while the MP52 integrated tank reduced this value to 79.95 W after a 180-minute retention time. These findings demonstrate that combining sensible and latent heat storage reduces thermal losses, improves discharge performance, and contributes to overall energy savings. The study also offers recommendations for the future optimization of PCM-enhanced hot water systems, emphasizing improved control strategies to increase efficiency, particularly in material selection, PCM deployment, and next-generation hot water storage designs.
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