摘要
提出一种填充三级相变材料的水平套管式储热器,并建立该储热器的综合性能评价指标,基于该指标数值预测和研究了分隔壁面、翅片布置和方向等参数对系统综合性能的影响。结果表明:分隔壁面对PCM的自然对流有明显的抑制作用,且相变温度越高,抑制效果越显著;相对于无翅片结构,在各级PCM中布置翅片的储热器的综合储热效率提高了约2.27倍;不同翅片布置方向下PCM液相率的变化可分为两个不同阶段,且均匀布置的翅片结构(Case2)具有较优的综合性能;各级PCM间熔化速率的不均匀性是制约系统整体储热性能的关键因素;Case5的翅片布置方式使各级PCM间熔化速率的均匀性明显改善,与Case2相比,其综合储热效率提高了28.30%。
A horizontal sleeve tube heat exchanger filled with three-layer phase change materials is proposed, and a comprehensive storage density evaluation criterion of the heat storage device is established. Based on the criterion, the effects of separated walls, fin arrangements and direction are numerically predicted and investigated. The results show that the natural convection of PCM (phase change material) is significantly suppressed by separated walls, and the higher the phase change temperature, the more significant the suppression effect. Compared with the sleeve tube heat exchanger without fins, the comprehensive thermal storage efficiency for the exchanger with fins in each layer PCM is improved by 2.27 times. The variations of PCM liquid fraction can be divided into two different stages under various fin arrangement directions, and the evenly arranged fin structure (Case2) has superior thermal storage performance. The non-uniformity of the PCM melting rate in each layer is a key factor that restricts the overall system performance of the thermal storage characteristics. Compared with Case2, the uniformity of the melting rate between different-layer PCMs can be significantly improved by Case5, and the comprehensive thermal storage efficiency is improved by 28.30%.
作者
王宁
张晨宇
徐洪涛
张剑飞
WANG Ning;ZHANG Chenyu;XU Hongtao;ZHANG Jianfei(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering,Shanghai 200093,China;MOE Key Laboratory of Thermo-Fluid Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,Shaanxi,China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2019年第A02期191-200,共10页
CIESC Journal
基金
国家重点研发计划项目(2018YFF0216000)
关键词
太阳能
传热
相变材料
翅片优化
数值模拟
solar energy
heat transfer
phase change material
fins optimization
numerical simulation
作者简介
第一作者:王宁(1995—),男,硕士研究生,tioddog@foxmail.com;通信作者:徐洪涛(1976-),男,博士,副教授,htxu@usst.edu.cn.
