Influence of thermal stratification on discharging process of molten salt in small single thermal storage tank

doi:10.11949/j.issn.0438-1157.20171275

Abstract

Abstract:

To observe the influence of thermal stratification on the discharging process of molten salt in small single thermal storage tank, the discharging process of molten salt with or without thermal stratification were investigated. The parameters including molten salt temperature, water temperature at the outlet of the heat exchanger and the cumulative heat discharging efficiency were analyzed in details. It was found that maintaining the thermal stratification of the molten salt during the heat discharging process is the key factor to improve the cumulative heat release efficiency of the single tank. The disturbance caused by the heat discharging of the immersed heat exchanger can destroy the molten salt thermal stratification, so it is necessary to optimize it. The results provide an effective basis for the optimization of small single thermal storage tank system with immersed heat exchanger.

Key words: thermal stratification, convection, heat transfer, mixing, molten salt in small single thermal storage tank, cumulative heat release efficiency

摘要：

为了探究温度分层对小型熔盐单罐释热过程的影响，对释热前单罐内熔盐有、无温度分层两种工况下的释热过程进行了实验研究。通过对隔板内外侧熔盐温度、换热器出口处水温、释热过程累积释热效率等参数进行分析发现：释热过程中维持熔盐稳定的温度分层是提高单罐释热效率的关键因素，而浸没式换热器取热时产生的扰动会破坏熔盐温度分层，影响释热效率，需要对其进行优化。研究结果为内置浸没式换热器的小型熔盐单罐系统的优化提供了有效依据。

关键词: 温度分层, 对流, 传热, 混合, 小型熔盐单罐, 累积释热效率

CLC Number:

CUI Ximin, LU Yuanwei, WU Yuting, MA Chongfang. Influence of thermal stratification on discharging process of molten salt in small single thermal storage tank[J]. CIESC Journal, 2018, 69(6): 2410-2416.

崔锡民, 鹿院卫, 吴玉庭, 马重芳. 温度分层对小型熔盐单罐释热过程影响[J]. 化工学报, 2018, 69(6): 2410-2416.

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