Heat release performance test of a single tank molten salt thermal storage system

doi:10.19799/j.cnki.2095-4239.2025.0949

Abstract

Abstract: This paper experimentally investigated the heat release performance of a single-tank molten salt storage system using a straight-tube heat exchanger, analyzing the temperature variation patterns during the heat storage, heat release, and static cooling processes. The experiments show that when the fan operates at full power, the system's maximum heat release power is 63.7 kW, the average heat release power is 46 kW, and the overall heat release efficiency reaches 88%, capable of heating cold water from 27°C to 64.4°C. During the heat release process, the molten salt temperature distribution is generally uniform, but near the air inlet, the temperature drops faster due to intense local heat exchange. In the 12-hour static cooling process, the molten salt temperature decreases linearly with a total drop of 36.8°C, the average cooling power is 4.8 kW, and significant vertical temperature stratification occurs, with a maximum temperature difference of 16.8°C. This study provides experimental support for the application of straight-tube heat exchangers in single-tank molten salt storage systems and offers reference value for regional heating and industrial heat storage engineering design.

Key words: Molten salt thermal energy storage, Single-tank system, Heat discharge performance, Straight-tube heat exchanger, Static cooling

CLC Number:

LI Wei, NIE YangBin, LI YunFei, LIU ShaoPeng, CHENG XiaoJun, ZHANG YongXue. Heat release performance test of a single tank molten salt thermal storage system[J]. Energy Storage Science and Technology, doi: 10.19799/j.cnki.2095-4239.2025.0949.

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