熔盐电磁感应加热系统的热性能分析

Analysis of thermal performance of electromagnetic induction basedmolten salt heating system

将电磁感应加热技术应用到低谷电加热熔盐储热供暖领域,搭建熔盐电磁感应加热实验系统,以感应加热器为研究对象,探究熔盐以及线圈冷却水在不同熔盐流速和线圈电流工况下的温度变化规律,计算加热效率和冷却水热损失率。结果表明:电磁感应加热器可以快速加热熔盐,熔盐温升主要集中在开始加热80~240 s之间,温升速率在100 s时最大;改变线圈电流或熔盐流速,可以产生不同终温的熔盐,流速0.177 m/s时,熔盐在不同电流下出口温度分别为201.452℃、203.891℃、207.599℃、212.975℃和221.454℃;熔盐流速一定,熔盐和线圈冷却水吸热量随线圈电流的增加而升高;线圈电流不变,熔盐吸热量随流速的增加而升高、线圈冷却水吸热量随流速增加而降低;熔盐流速0.296 m/s、线圈电流600A时,熔盐加热效率为69.28%,线圈冷却水热损失率为16.45%。

This paper concerns the application of the electromagnetic induction heating technology in heating molten salt in a heat storage system. An experimental system was set up for electromagnetic induction heating of molten salt and temperature variation of molten salt and coil cooling water under different molten salt velocity and coil current conditions were investigated. The results showed that the electromagnetic induction heater can heat the molten salt quickly. The temperature rise of molten salt occurred mainly in the first 80-240 s after starting the heating process, and the temperature rising rate reached maximum at ~100s. A change in the coil current or molten salt velocity can produce molten salts with different final temperatures. When the velocity was 0.177m/s, the outlet temperature of molten salt at different currents was 201.45 ℃, 203.89 ℃, 207.60 ℃, 212.98 ℃ and 221.45 ℃. When the velocity of molten salt was constant, the heat absorption of molten salt and coil cooling water increased with increasing coil current. When the coil current was constant, the heat absorption of molten salt increased with increasing velocity, while the heat absorption of cooling water decreased. When the velocity of molten salt was 0.296 m/s and the current of coil was 600 A, the heating efficiency of molten salt was 69.28% and the corresponding heat loss of the cooling water was 16.45%.