储能科学与技术 ›› 2022, Vol. 11 ›› Issue (11): 3558-3565.doi: 10.19799/j.cnki.2095-4239.2022.0248

• 储能系统与工程 • 上一篇    下一篇

肋片增强式梯级相变储热系统放热特性的三维数值

沈永亮(), 张朋威, 刘淑丽()   

  1. 北京理工大学机械与车辆学院,北京 100081
  • 收稿日期:2022-05-09 修回日期:2022-05-18 出版日期:2022-11-05 发布日期:2022-11-09
  • 通讯作者: 刘淑丽 E-mail:shenyl0104@163.com;shuli.liu@bit.edu.cn
  • 作者简介:沈永亮(1996—),男,博士研究生,研究方向为相变储能,E-mail:shenyl0104@163.com
  • 基金资助:
    国家自然科学基金项目(52178063)

Three-dimensional numerical study of discharging characteristics of a fin-enhanced cascaded latent heat storage system

Yongliang SHEN(), Pengwei ZHANG, Shuli LIU()   

  1. School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
  • Received:2022-05-09 Revised:2022-05-18 Online:2022-11-05 Published:2022-11-09
  • Contact: Shuli LIU E-mail:shenyl0104@163.com;shuli.liu@bit.edu.cn

摘要:

梯级相变储热技术已被证明是解决相变材料导热性能差的重要方法。已有的关于梯级相变储热系统的数值研究通常是基于一维或二维数学模型完成的,大部分的研究聚焦于系统的储热过程。本工作设计了一种肋片增强型三管式梯级相变储能系统,并建立了三维数值模型。然后研究了系统放热过程中各级PCM的性能变化规律,探究了传热流体进口温度和PCM初始温度对系统放热速率的影响规律。结果表明,在放热过程中,各级PCM相变不会同时发生,受到储热材料的相变温度和潜热的影响最大。传热流体进口流速的增大会提高相变材料的放热速率,但随着流速的进一步增加,放热速率的提高程度明显减弱。相变材料的初始温度对显热放热过程具有一定的影响,但对于潜热放热阶段影响较小。

关键词: 梯级相变储热, 肋片, 储热器, 数值模拟

Abstract:

Cascaded latent heat storage technology has been proven as an effective method for solving the poor thermal conductivity of phase change materials (PCMs). Previous numerical studies on cascaded latent heat storage systems were based on one-or two-dimensional mathematical models, and most of them focused on the charging process. In this paper, a fin-enhanced three-tube cascaded latent heat storage system is proposed, and a three-dimensional numerical model is established to study the thermal performance of PCMs at each stage of the discharging process and to explore the effect of the inlet velocity of the heat transfer fluid and initial temperature of PCMs on system thermal performance. The results show that during the discharging process, the phase change of PCMs at each stage do not occur simultaneously, and the PCMs are mainly affected by the phase change temperature and latent heat. The increase of the inlet velocity of the heat transfer fluid increases the discharging rate of the PCMs. With a further increase of the inlet velocity, the enhancement effect of the discharging rate is weakened. The initial temperature of the PCMs has a certain influence on the sensible heat discharging process but limitedly affects the latent heat discharging stage.

Key words: cascaded latent heat storage, fins, heat storage unit, numerical simulation

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