Temperature and salt concentration behavior of a compact rectangular salinity gradient solar pond
1Department of Mechanical Engineering, Dr.N.G.P. Institute of Technology, Coimbatore, 641048, India
2School of Mechanical Sciences, Bannari Amman Institute of Technology, Sathyamangalam, 638401, India
3Department of Mechanical Engineering, Sri Ramakrishna Institute of Technology, Coimbatore, 641010, India
4Department of Nuclear and Renewable Energy, Ural Federal University, Ekaterinburg, Yeltsin, 620075, Russia
5Department of Mechanical Engineering, PSV College of Engineering and Technology, Krishnagiri, 635108, India
J Ther Eng 2024; 2(10): 386-395 DOI: 10.18186/thermal.1448665
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Design of economical and effective solar ponds which are useful thermal energy storage devices, remains a huge challenge. The present work aims at investigating the thermal performance of low cost mini salt gradient solar pond. The portable pond was fabricated as a rectangular configuration having a volume of 0.5m3. Polystyrene and high density polyethylene sheets were employed for insulating the walls. The top of the pond was covered with a slender glass so that the dust accumulation could be prevented without affecting the absorption of solar radiation. Sodium chloride salt was used as the medium and the three salt gradient regions namely lower convective, non-convective, and upper convective regions were established through injection filling technique. The temperature and salt gradient data were observed experimentally for a period of 20 days at Coimbatore, India. The pond could absorb significant amount of available radiation (around 65%) and the maximum temperature of the pond was observed to be 49oC. Frequent washing of the water surface is necessary to maintain stable salt gradient. Nevertheless, portable pond fabricated with low cost materials exhibited good potential of storing solar energy for solar thermal applications.