在表面粗的太阳能空气加热系统中应用三角管道:数值调查
Rajneesh Kumar1, Palvai Srinivas Reddy2, Manjeet Kharub3
1Chitkara University Institute of Engineering & Technology, Chitkara University, Rajpura, 140401, Punjab, India.
概括
这项研究通过增加圆腔表面粗度来增强太阳能空气加热器 (SAH),显著提高热性能和热液压效率,以更好地利用太阳能.
科学领域:
- 可再生能源工程可再生能源工程
- 热科学 热科学 热科学
- 流体动力学 流体动力学
背景情况:
- 传统的太阳能空气加热器 (SAH) 的热性能低于最佳.
- 提高能源采集和传输效率对于空间加热和干燥等SAH应用至关重要.
研究的目的:
- 通过表面修改来提高太阳能空气加热器 (SAH) 的热性能.
- 调查圆腔表面粗度对SAH效率的影响.
主要方法:
- 计算流体动力学 (CFD) 代码的开发和验证.
- 圆腔粗度尺寸的参数研究:相对流向距离,相对腔深度和相对横向距离.
- 对CFD模拟的实验验证.
主要成果:
- 与传统设计相比,拟议的表面粗性显著提高了2.57倍的热传递.
- 这种增强带来了1.75倍更高的热液压性能.
- 在特定无维参数下观察到最佳性能:相对流量距离为10,相对腔深为0.038,相对横向距离为10.
结论:
- 圆腔的表面粗性通过诱导流和流,有效地提高了SAH的热性能.
- 改进的热性能伴随着增加的压力损失 (2.3倍).
- 优化的SAH设计可大大提高整体能源利用效率.
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