化工学报 ›› 2011, Vol. 62 ›› Issue (S1): 37-41.

• 流体力学与传递现象 • 上一篇    下一篇

套管式相变储能单元的强化换热

夏莉,张鹏,王如竹   

  1. 上海交通大学制冷与低温研究所,上海200240
  • 出版日期:2011-07-03 发布日期:2011-07-03

  • Online:2011-07-03 Published:2011-07-03

摘要:

利用数值模拟方法研究了四种相变储能单元的放热性能。储能单元包括:光管中填充石蜡、翅片管中填充石蜡、光管中填充石蜡/膨胀石墨复合相变材料、翅片管中填充石蜡/膨胀石墨复合相变材料。结果表明添加5%(质量分数)膨胀石墨的强化效果与设计翅片的强化效果相当,而强化效果最好的是同时采用上述两种强化换热措施。换热流体流量越大,强化换热措施对储能单元的放热性能影响越大。在换热流体流量为0.02 m·s-1时,第四种储能单元的放热时间比第一种减少50%,同时有效温区内的温度最多可提高5 K。储能单元进口水温与相变储能材料熔点间温差越大,强化换热的作用越明显。强化换热的措施在换热流体流量大及换热温差大的储能单元中作用显著。

关键词: 潜热储能, 强化换热, 翅片, 膨胀石墨

Abstract:

In order to investigate the most effective means of heat transfer enhancementfour different kinds of heat storage unitsthe bare tube with pure paraffinthe finned tube with pure paraffinthe bare tube with paraffin/expanded graphite composite material and the finned tube with paraffin/expanded graphite compound material were studied numerically and the performance was compared.The heat transfer performance of the fourth unit was the best one for all the units,while that of the second unit and the third unit were similar and were both better than the first unit.When the mass flow rate of heat transfer fluidHTFat the inlet was 0.02 m·s-1the heat retrieval duration for the fourth unit was only half of that in the first unit.Moreoverthe temperature of the HTF at the outlet was nearly 5 K higher than that in the first unit.The heat transfer enhancement became more evident with increasing the mass flow rate and decreasing the temperature of the HTF at the inlet.

Key words: 潜热储能, 强化换热, 翅片, 膨胀石墨