Comparative investigation on the heat transfer performance of an energy storage system with a spiral tube and straight tube:An experimental approach

作     者：MAO QianJun CAO Yan LI Tao 

作者机构：School of Urban ConstructionWuhan University of Science and TechnologyWuhan 430065China 

出 版 物：《Science China(Technological Sciences)》 (中国科学（技术科学英文版）)

年 卷 期：2023年第66卷第1期

页      面：71-85页

核心收录：

学科分类：080701[工学-工程热物理] 08[工学] 0807[工学-动力工程及工程热物理] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the National Natural Science Foundation of China (Grant No. 51876147)。 

主　　题：thermal energy storage visualization experiment PCM spiral tube straight tube 

摘      要：Latent heat thermal energy storage systems can effectively fill the gap between energy storage and application, and phase-change materials(PCMs) are crucial media for storing thermal energy. Therefore, how to maximize the utilization efficiency of PCMs has attracted widespread attention. In this study, the thermal behavior of two thermal storage units employing a spiral tube and straight tube as heat transfer tubes was experimentally researched and comprehensively compared. Stefan numbers were used to investigate the impact of the heat transfer fluid temperature on the PCM melting process. The temperature distribution of PCMs,temporal evolution of the melting front, and temperature variations of measurement points in both tanks were compared. The average temperature and energy storage of PCMs were calculated to evaluate the thermal performance of different configurations. The results indicate that compared to cylinder B(with a straight tube), the energy storage in cylinder A(with a spiral tube)increased by 78.8%, 38.5%, and 19.6% at Stefan numbers of 1.08, 1.28, and 1.48, respectively. Moreover, the increase in the Stefan number simultaneously ascended the average temperature and energy storage of PCMs in containers A and B, causing the shortening of the melting time. When the Stefan number was increased from 1.28 to 1.48, the storage capacity was raised from3233.18 to 3463.8 k J, and the total melting time was decreased by 34.2% from 547.5 to 360 min after the PCM was loaded in cylinder A. The research results lay a certain foundation for a deeper study of enhanced heat transfer in spiral tubes.