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在带有垂直头的水平蛇形管束中,流动的稳定性和分布
Viktoria Illyés1, Stefan Thanheiser1, Felix Ettlinger1
1Institute of Energy Systems and Thermodynamics, TU Wien, Getreidemarkt 9/BA/E302, Vienna, A-1060, Austria.
Heliyon
|December 13, 2024
概括
基于粒子的热能存储 (TES) 系统在独特的热交换器设计中面临流量分配的挑战. 模拟显示了大量流量失衡,特别是在蒸汽生成和部分负载运行期间,影响了系统效率.
科学领域:
- 可再生能源系统可再生能源系统
- 热能储存 (TES) 是一种热能储存技术.
- 流体动力学 流体动力学
背景情况:
- 基于粒子的系统,如sandTES,将热能储存与可再生能源相结合.
- 该系统使用带有垂直头和水平管的流体床换热器,设计缺乏既定的原则.
- 调查这种非传统换热器的流量分布和不稳定性对于扩展至关重要.
研究的目的:
- 分析用于sandTES系统的宏大垂直头部和水平管束的流量分布不平衡和不稳定性.
- 用模拟来评估这种换热器设计的扩展潜力.
- 识别和提出设计修改,以改善流量分配.
主要方法:
- 利用APROS模拟来进行热交换机的稳定状态和动态分析.
- 在各种条件下研究了流动行为:蒸汽产生,凝结,启动,关闭和部分负载.
- 评估了标题设计修改对流失平衡的影响.
主要成果:
- 在蒸汽生成过程中,在高层换热器中观察到显著的质量流失平衡 (低至55%的差异).
- 较小的热交换器显示出较少的不平衡 (88%),而凝结导致不显著的不平衡.
- 动态模拟表明,在短暂运行过程中,特别是部分负载时,不稳定性和流量逆转.
- 标题修改使失衡因子从55%提高到88%.
结论:
- 研究的热交换器设计表现出大量的流量分配挑战,特别是在蒸汽生成和瞬态状态期间.
- 扩大规模需要仔细考虑流动不稳定性和不平衡性.
- 标题设计修改提供了一个可行的解决方案,以减轻流量分配不当并提高系统性能.
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