Abstract
The increased depletion of fossil fuels needs alternatives like solar energy to address daily demands. However, solar energy is intermittent, hence it is integrated with thermal energy storage (TES) systems. Phase change materials (PCM) are used in TES systems, but they suffer from meagre thermal conductivity, leading to less fusion. This study enhances PCM fusion using four different cases, namely, case 1 (without fins), case 2 (with two fins placed near the top), case 3 (with two fins placed near the bottom), and case 4 (with two fins placed near the top and bottom), respectively. The study is done with heat transfer fluid (HTF) temperature at 70 °C and 75 °C with a 30 LPH flow rate. Case 4 displayed a melting time reduction of 34%, and 47.7% when compared with case 1. It is also found with high thermal efficiency and effectiveness. The results indicate that case 4 is effective in expediting fusion and enhancing storage performance due to optimal fin placement, hence suggested for solar applications.
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Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Abbreviations
- HTF:
-
Heat transfer fluid
- PCM:
-
Phase change material
- TES:
-
Thermal energy storage
- \(\:\dot{m}\) :
-
Mass flow rate (kg. sec−1)
- Cpl :
-
Liquid PCM specific heat capacity (kJ. kg−1. K−1)
- Cps :
-
Solid PCM specific heat capacity (kJ. kg−1. K−1)
- Cpw :
-
Water specific heat capacity (kJ. kg−1. K−1)
- Fi :
-
Melt fraction
- K:
-
PCM thermal conductivity (W. m−1. K−1)
- L:
-
Latent heat (kJ. kg−1)
- m:
-
Mass (kg)
- Qin :
-
Heat supplied (kW)
- t:
-
Time (sec)
- Tini :
-
PCM initial temperature (K)
- Tl :
-
Liquidus temperature (K)
- Tpcm :
-
PCM temperature (K)
- Ts :
-
Solidus temperature (K)
- Twi :
-
HTF inlet temperature (K)
- Two :
-
HTF outlet temperature (K)
- \(\eta\) :
-
Efficiency
- ϵ:
-
Effectiveness
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Authors would like to thank SRM Institute of Science and Technology, Ramapuram Campus, Chennai, for providing all technical and administrative supports in completing this research work in a successful manner.
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B.M.S.P., M.V., M.M., A.A., D.B., U.K., A.K., and V.L. wrote the main manuscript text . All authors reviewed the manuscript.
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Swami Punniakodi, B.M., Veeramanikandan, M., Manickam, M. et al. Effect of fins in enhancing phase change material fusion in a spherical thermal energy storage container. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38262-8
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DOI: https://doi.org/10.1038/s41598-026-38262-8


