Experimental Study on the Molten Salt at Micron Scale during the Melting Process  

作　　者：TIAN Ziqian LIAO Zhirong XU Chao FANG Yongzhe JIANG Kaijun YUAN Mengdi 

机构地区：[1]Key Laboratory of Power Station Energy Transfer Conversion and System,Ministry of Education of China,School of Energy Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China

出　　处：《Journal of Thermal Science》2024年第1期70-85,共16页热科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.51821004 and No. 51876061)。

摘　　要：The investigation of the melting behaviors of the molten salt at micron scale during the melting process is critical for explaining the solid-liquid phase transition mechanism.In this paper,a novel experimental system and analysis method were proposed to study the melting process with three heating rates in the range of1-10℃/min of the solar salt at micron scale.The solid-liquid boundary morphology and phase transition kinetics of molten salt particles were focused on.Meanwhile,the correlations between liquid fraction,temperature and time under different heating rates were studied.The solid-liquid boundary morphology was depicted by the visualized experimental set-up,and the instantaneous liquid volume fraction during the non-isothermal phase transition was obtained.Then,the correlation between temperature and liquid volume fraction was proposed to reveal the evolution of the solid-liquid boundary with temperature at different heating rates.Furthermore,the non-isothermal phase transition kinetic equation was established by introducing a constant parameter(V_(a,b)),and more kinetic parameters such as 1g V_(a,b) and-lg V_(a,b)/b were studied.The results showed that the exponent b is not sensitive to the heating rate with a range of 3-5 for solar salt particles.However,the heating rate influences the value of V_(a,b) and presents a positive relationship.Besides,the non-isothermal phase transition kinetic equations at different heating rates in the range of 1-10℃/min can be quickly predicted by the proposed improved experimental test method.This study could fill the research insufficiency and provide significant guidance for future research on the solid-liquid transition mechanism of molten salts at micron scale.

关 键 词：molten salt non-isothermal phase transition solid-liquid boundary morphology liquid volume fraction micron scale melting process 

分 类 号：TK11[动力工程及工程热物理—热能工程]