Transient analyses of a molten salt heat storage tanks

doi:10.12028/j.issn.2095-4239.2017.0011

Abstract

Abstract: In this work, a computational fluid dynamics model is developed to analyze the cooling process of a molten salt tank during a standby period. The heat losses and temperature distribution under different conditions are obtained through the calculations. It is shown that the temperature distribution in the tank is mostly homogeneous, except for a temperature stratification closed to the bottom of the tank. Under the same conditions, the higher the level of molten salt, the longer time needed for the solidification of molten salt. For the cold tank at low molten salt level (290 ℃, 0.9 m), the estimated onset of solidification occurs in 3.8 days, and all the molten salt is solidified in 19.3 days.

Key words: thermal energy storage system, molten salt, cooling process, numerical simulation, solar energy

GU Qingzhi, ZHANG Yanmei, GUAN Hongyang, ZHANG Yawei, DUAN Yang, LIAO Wenjun. Transient analyses of a molten salt heat storage tanks[J]. Energy Storage Science and Technology, 2017, 6(4): 782-788.

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