摘要
建立同心套管相变蓄热单元的二维模型,并与文献对比验证,完成网格无关性和时间步长独立性验证后,数值模拟分析模型结构和流体入口速度对蓄热特性的影响,探究导热系数和相变材料的熔点对放热特性的影响。研究结果表明：采用波节管代替光管可优化蓄热单元的蓄热特性,且3#波节管的换热性能最优,相比于光管,蓄热时间可缩短39%;其他条件不变时,增加传热流体（heat transfer fluid,HTF）的导热系数,蓄热单元的放热效率先增后降,存在最佳值;当相变材料（phase change materials,PCM）的导热系数大于HTF时,继续增加PCM的导热系数会使放热效率下降;随着PCM熔点的增加,有效放热时间先增后减,在熔点为603 K时,放热效率达到最大值0.82。
A two dimensional model for a concentric tube latent heat storage unit was established. Based on meshindependence and time-step independence check,the model is used to investigate the effect of model structure and fluidvelocity on the heat charge performance. The effect of thermal conductivity and phase change material melting point onthe heat discharge performance is also studied. The results showed that the heat charge performance of thermal storageunit is optimized using the corrugated tube compared of light tube. The performance of 3# corrugated tube is the best,forcharge time is shortened by 39% compared to the light tube. Heat efficiency of heat storing unit first increased and thendecreased with the increasing thermal conductivity of HTF. There exists an optimum value when the other conditionremain unchanged. The efficiency of the heat release will decrease with the increasing thermal conductivity of PCM whenthe thermal conductivity of PCM is greater than HTF. The effective discharge time first decreased and then decreasedwith the increase of the melting point of PCM. The teat efficiency reaches the maximum value of 0.82 when the meltingpoint reaches 603 K.
作者
程友良
韩健
张金生
Cheng Youliang;Han Jian;Zhang Jinsheng(School of Energy Power and Mechanical Engineering, North China Electric Power University, Baoding 071003, China;ShenHua GuoHua （ Beijing ） Electric Power Research Institute Limited Company, Beijing 100025, China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2018年第5期1237-1244,共8页
Acta Energiae Solaris Sinica
基金
中央高校基本科研业务费专项(2016XS107
2017MS121)
关键词
蓄热
相变材料
熔融盐
数值模拟
heat storage unit
phase change materials
molten salt
numerical simulation
