Predictive modeling of solidification characteristics of a phase change material in a metallic spherical capsule fitted with fins of different lengths

ABSTRACT

This study investigates the effect of fin length on solidification characteristics of deionized water filled in a stainless steel spherical capsule immersed in a constant temperature bath. Alongside, Box-Benkehn experimental design is employed to develop mathematical models for predicting solidification duration using response surface regression. Experiments are carried out at three different bath temperatures (−6°C − 9°C and −12°C). Four radial fins of 3 mm diameter made of copper are fixed on the inner surface of the spherical capsule. Three fin-lengths of 7.5 mm, 13.5 mm, and 19.5 mm are chosen which corresponds to the annulus volume margins of 50%, 75%, and 90% respectively measured from the inner surface of the capsule. Results revealed that the fin length has no significant effect on the duration of solidification. The individual as well as interactive effects of frozen mass fraction and bath temperature were found to be statistically significant. The models developed were found to be statistically significant at a 99% confidence level and the confirmatory experiments validated that the developed models were able to predict the solidification time with reasonable accuracy. It was found that there is an improvement in solidification duration in the range between 17% and 21% using the combinations predicted by the desirability approach when compared to a capsule fitted with no fin under similar conditions. The spherical capsule fitted with a fin of length 16.5 mm shows a reduction of 21% in solidification duration to achieve 96% of frozen mass at a bath temperature of −12°C.

KEYWORDS:

• Phase change material
• thermal energy storage
• solidification
• fins
• spherical capsule
• response surface methodology
• modeling

Additional information

Funding

The authors received no funding for this research.

Notes on contributors

Premnath Doss

Premnath.D obtained his B.E. (Mechanical Engineering) and M.E. (Thermal Engineering) from the Madurai Kamaraj University (2000) and Anna University,Chennai (2004) respectively. He has two decades of experience in teaching and eight years of research. He is working as Assistant Professor at SRMIST, Chennai since 2009. The major research area is PCM based cold thermal energy storage, IC engines.

Chandrasekaran Ponnusamy

Chandrasekaran.P obtained his B.E (Mechanical Engineering) and M.Tech(Mechanical Engineering) from the Annamalai University(1986) and IIT, Madras(1996)  respectively. He received Ph.D (PCM based thermal storage) from SRM Institute of Science and Technology (SRMIST), Chennai (2015). He has three decades of experience in teaching and twelve years of research. He is working as Associate Professor at SRMIST, Chennai since 2007. The major research area is PCM based thermal energy storage,IC engines, nanofluids. He has filed eight patents and one has been awarded. He is a member of IE, SESI, SAE and ISTE.

Ganapathy Subramanian Lalgudi Ramachandran

Ganapathy Subramanian.L.R obtained his B.E (Mechanical Engineering) and M.E(Aeronautical  Engineering) from the Regional Engineering college,Durgapur(1988) and Anna University(1990) respectively. He received Ph.D (Air pollution modeling for point source emissions) from Anna University,Chennai(2008). He has three decades of experience in teaching and twenty years of research. He is working as Professor and Head of Department of Aerospace Engineering at SRMIST, Chennai since 1990. The major research area is aerospace structures, environmental engineering, air pollution modeling. He is a member of FIE and ISTE.