太阳能空气加热器的热传递增强使用囊形流器:数值分析
N Madhwesh1, K Vasudeva Karanth1, Shiva Kumar2
1Department of Mechanical and Industrial Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India.
Scientific reports
|May 2, 2025
概括
将囊形的流器添加到太阳能空气加热器中,通过破坏层状亚层来改善热传递. 45°的最佳定向角度和特定的轮机尺寸显著提高了热性能和功率效率.
科学领域:
- 可再生能源工程可再生能源工程
- 热传递增强 热传递增强
- 太阳能热系统 太阳能热系统
背景情况:
- 太阳能集热器中的层状子层阻碍了热传输.
- 人工粗,特别是轮机,可以增强热传输.
- 囊形轮机正在研究太阳能空气加热器的性能.
研究的目的:
- 为了数值地研究太阳能空气加热器的热性能,使用囊形的流器.
- 为了优化轮机的方向角度和几何参数.
- 评估轮机对传热系数,流量参数和能量效率的影响.
主要方法:
- 在带有囊轮机的太阳能空气加热器中对流量和传热的数值模拟.
- 轮机定向角度的变化 (0°90°在15°的步骤).
- 优化轮机排列,俯冲比和高度比.
主要成果:
- 对于所有测试的雷诺兹数 (300021,000) 在45°方向角度实现的最佳热性能.
- 超过45°增加了因流量阻塞而导致的动功率.
- 两排的距离比为0.05和高度比为0.006,产生了15.76%的热增强和52.64%的功率效率提高.
结论:
- 囊形的轮机有效地提高了太阳能空气加热器的热性能.
- 轮机的方向和几何参数极大地影响了效率.
- 优化的轮机设计比基本型号提供了显著的改进.
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