太阳能空气加热器具有离散的D形肋骨作为人工粗的热液压性能
Nitesh Dutt1, Ankush Jageshwar Hedau2, Ashwani Kumar3
1Department of Mechanical Engineering, College of Engineering Roorkee, COER University, Roorkee, Uttarakhand, India.
概括
这项研究以数值方式研究了太阳能空气加热器 (SAH) 性能与D形肋骨. 确定了最佳配置,并开发了Nusselt数和摩擦因子的相关性,以提高热液压效率.
科学领域:
- 可再生能源工程可再生能源工程
- 热传递热量转移的方法
- 流体动力学 流体动力学
背景情况:
- 太阳能空气加热器 (SAH) 对可再生能源应用至关重要.
- 提高SAH热液压性能是提高效率的关键.
- 肋骨通常用于增加SAH管道中的热传递.
研究的目的:
- 为了数值地研究太阳能空气加热器管道的热液压性能.
- 分析离散的D形肋骨对传热和流体流动的影响.
- 为了确定最佳的肋骨配置,并开发预测相关性.
主要方法:
- 使用ANSYS Fluent 2020 R2.2.进行数值调查.
- 对肋半径与横斜率比 (r/Pt) 和纵斜率与肋半径比 (Pl/r) 的参数研究.
- 数值结果与实验数据对努塞尔特数 (Nu) 的验证.
主要成果:
- 努塞尔特数 (Nu) 和摩擦因子 (f) 随着Pl/r的增加而下降.
- 在r/Pt = 0.25和Pl/r = 4的条件下达到最佳的热液压性能,最大性能参数为1.12.
- 与CFD结果相比,Nu和f的相关性显示出高准确度 (Nu的±2%,f的±2.7%).
结论:
- 离散的D形肋骨显著影响SAH热液压性能.
- 该研究为SAH设计提供了优化的参数和验证的相关性.
- 这些发现有助于开发更高效的太阳能空气加热系统.
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