对卵石太阳能热收集器的热性能进行实验和数值分析
N Channa Keshava Naik1, R Krishna Priya2, Ümit Ağbulut3
1Department of Mechanical Engineering, BGS College of Engineering and Technology, (Affiliated to Visvesvaraya Technological University, Belgaum), Bengaluru, 560086, Karnataka, India.
Heliyon
|February 5, 2024
概括
这项研究建议在太阳能平板收集器中使用卵石作为替代的吸收材料. 与传统材料相比,涂层石显示出轻微的效率损失,但对于综合建筑设计来说,它具有显著的优势.
科学领域:
- 可再生能源工程可再生能源工程
- 材料科学 材料科学 材料科学
- 建筑集成光伏系统的建设
背景情况:
- 传统的太阳能平板收集器通常使用或铜等材料作为吸收器.
- 将太阳能热系统集成到建筑设计中需要创新的材料和配置.
- 与传统的吸收材料相比,小石提供了更高的特定热容量.
研究的目的:
- 为了研究使用卵石作为替代吸收材料的太阳能平板收集器的性能.
- 为了比较涂层和未涂层卵石吸收器与常规材料的效率.
- 为了评估运行参数 (如流量和收集器倾斜) 对系统性能的影响.
主要方法:
- 用涂层和未涂层石吸收器测试太阳能平板收集器的实验测试.
- 不同的操作参数,包括吸热介质的流量和收集器倾斜.
- 使用计算流体动力学 (CFD) 建模进行数值分析,以优化设计.
主要成果:
- 在0.6L/分钟流量下,观察到常规吸收器的最大温度差异约为8°C.
- 涂层和未涂层的卵石吸收器显示最大温度差异分别为7°C和5.5°C.
- 与传统吸收器相比,涂层卵石吸收器的平均效率差异仅为5.82%,而非涂层卵石的效率则优于15.68%.
结论:
- 在太阳能平板集热器中用涂层卵石取代传统的吸收器,可实现最小的5.82%的效率损失,并带来显著的好处.
- CFD 建模提供了准确的预测,并可用于进一步优化基于石的太阳能集热器设计.
- 采用涂层卵石的体集成太阳能收集器为可持续建筑能源解决方案提供了一个有希望的途径.
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