扭管螺旋线圈的热流体特性和运动分析
1Department of Refrigeration and Air Conditioning Technology, Faculty of Technology and Education, Helwan University, 11282, Cairo, Egypt. Mahmoudabdelmagied@techedu.helwan.edu.eg.
Scientific reports
|November 13, 2024
概括
这项研究通过使用有三角形和方形内部形状的扭曲螺旋管来增强热传输. 扭管螺旋线圈 (TTHC) 设计提高了热性能,在传热率上取得了显著的收益.
科学领域:
- 热力学和热转移热力学
- 流体动力学 流体动力学
- 能源系统工程 能源系统工程
背景情况:
- 传统的热交换器在实现最佳热流体性能方面经常面临局限性.
- 在螺旋线圈内整合扭曲通道可以增强流体旋转和流.
- 扭管螺旋线圈 (TTHC) 是一种创新的方法,可以提高传热效率.
研究的目的:
- 实验性地研究一种新的扭管螺旋线圈 (TTHC) 的电力和热流体特性.
- 评估不同内管截面 (三角形和正方形) 和斜率对传热和流体摩擦的影响.
- 开发新的相关性来预测Nusselt数和TTHC的环形中的摩擦因子.
主要方法:
- 对六种TTHC几何形状的实验分析,其间距比率不同 (36毫米,54毫米和∞),内管形状不同 (三角形和方形).
- 进行了反流排列的实验,对内部和环状液体进行了特定范围的雷诺兹数 (Rei: 10,30037,800; Reo: 240017,600).
- 测量和分析热传递 (努塞尔特数),摩擦系数,热性能系数和能量效率.
主要成果:
- 与光滑管相比,扭曲型材的Nusselt数增加了41.5%,高达5%.
- 热性能系数达到三角形内管1.3的值,方形内管1.25的值,距离比为36毫米.
- 基于实验数据,开发了 annulus Nusselt 数 (Nuo) 和摩擦因子 (fo) 的新相关性.
结论:
- 在螺旋线圈中整合扭曲通道显著提高了传热性能.
- 与光滑管相比,具有三角形和方形内部配置的TTHC显示出优越的热效率.
- 该研究为优化TTHC设计在各种热交换应用中提供了有价值的数据和相关性.
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