摘要
实验测试了两种相变温度分别为-5.4℃和-9.6℃、相变焓分别为132 kJ/kg和173 kJ/kg的十三烷和十二烷在不同组合模式下对蓄冷装置温度变化的影响。结果表明,十三烷在外层、十二烷在内层的组合模式,尽管总相变潜热在所有组合中仅排第三,但蓄冷装置将内壁温度控制在0℃以下的时间最长,与双层同为十二烷的工况相同,高于双层同为十三烷及十三烷在内十二烷在外层的模式。相变温度更高的材料在外层,可以降低环境热量传递至蓄冷装置内部的速率,延长蓄冷时间,有利于提高蓄冷装置的性能。
Cold storage using phase change materials(PCMs) has wide applications on the transportation of food and medical products. This article presents a study on the performance of a cold storage device with two PCMs in a layered structure. Tridecane and dodecane were used as the PCMs, which have phase change temperatures and phase change enthalpies of-5.4 ℃ and 132 kJ/kg, and-9.6 ℃ and 173 kJ/kg, respectively. The main objective of the study was to find the best combination of the two PCMs giving the longest storage period. The results showed that the combination with tridecane placed outside and dodecane inside gave the longest time for the inner wall temperature to change from-15 ℃ to 0 ℃ although the combination only had the 3rd largest total latent heat. Same conclusions were obtained with pure dodecane, which was longer than the unit with pure tridecane and tridecane located outside layer and dodecane inside. Placing the PCM with a higher phase change temperature in the outside layer reduced the heat transfer rate from the ambient to the internal core of the cold storage unit, leading to an increase in the cold storage period and improvement in the cold storage performance.
出处
《储能科学与技术》
CAS
CSCD
2017年第4期696-700,共5页
Energy Storage Science and Technology
基金
广东省应用型科技研发专项(2016B020243008)
广东省自然科学基金(2014A030312009)项目
关键词
相变材料
蓄冷
多层结构
phase change materials
cold storage
multi-layer structure