对纳米流体进行热传递增强的关键见解
Abdul Hai Alami1,2, Mohamad Ramadan3,4, Muhammad Tawalbeh5,6
1Sustainable and Renewable Energy Engineering Department, University of Sharjah, P.O. Box 27272, Sharjah, United Arab Emirates. aalalami@sharjah.ac.ae.
Scientific reports
|September 15, 2023
概括
这项研究批判性地检查了热交换器中纳米流体的热传递增强. 重新计算显示,收益明显低于报告,质疑纳米流体有效性的广泛声称.
科学领域:
- 热力学是一种热力学.
- 流体力学 流体力学 流体力学
- 材料科学 材料科学 材料科学
背景情况:
- 许多出版物声称使用纳米流体的热交换器显著增强热传输.
- 纳米流体被定义为具有纳米级固体颗粒低体积分数 (≤5%) 的流体.
- 在现有文献中,报告的对流传热传递的增强是相当大的.
研究的目的:
- 批判性地调查纳米流体所声称的传热增强效果.
- 重新评估先前研究中的基本传热计算和实验方法.
- 促进关于纳米流体在传热方面的实际有效性和局限性的科学辩论.
主要方法:
- 对最近关于热交换器中纳米流体的出版物的批判性审查.
- 根据选定的论文的方法,重新计算传热系数.
- 对发现的统计分析和对实验设置和应用的评估.
主要成果:
- 确定了对流传传热传递机制的不一致性和潜在的基本理解不足.
- 重计算的传热增强值明显低于报告值 (例如,约3.5%和-4%) (例如,27%,48%).
- 在地理来源,实验设置和报告发现的实际应用方面观察到的局限性.
结论:
- 纳米流体的实际传热增强可能在当前文献中被大大高估了.
- 纳米流体可能不是唯一或最有效的解决方案来增强热交换器中的对流热传递.
- 纳米颗粒的物理性质和高成本 (例如,黄金,钻石,银) 带来了重大的商业化挑战.
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