在螺旋结构的垂直头部中对两相流量分布的实验研究.
Moojoong Kim1, Jongsoo Jeong2, Kiyoshi Saito2
1Research Institute for Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, 169-8555, Japan.
Heliyon
|July 18, 2024
概括
垂直头部的新型螺旋结构显著改善了微通道换热器中的制冷剂分配. 这种增强对于优化空调系统的性能至关重要,因为它可以确保连续两相流量.
科学领域:
- 热力学和热传递 热力学和热传递
- 微通道中的流体动力学
- 制冷和空调系统的制冷和空调系统.
背景情况:
- 垂直头部对于在微通道换热器中分配双相制冷剂至关重要.
- 最佳性能依赖于冷却剂分布的均性,这受头部几何形状和流速的影响.
- 现有的设计在实现统一的分配方面面临挑战,这会影响整体系统的效率.
研究的目的:
- 为了研究垂直头部内螺旋结构对双相流量分布的影响.
- 为了比较螺旋式头部与传统的直立垂直头部的分布性能.
- 评估不同质量流速和蒸汽品质对流动特性的影响.
主要方法:
- 使用了一个模拟微通道换热器的实验设置.
- 在各种输入条件下测量了螺旋式垂直头部的分布特征 (质量流量:50-100公斤/小时;蒸汽质量:0.1-0.2).
- 性能与具有相同横截面特性的直立垂直头部进行了基准测试.
主要成果:
- 螺旋结构促进了独特的流动模式,增强了两个制冷剂相的混合.
- 与直线头相比,螺旋式头部观察到较少的惯力.
- 螺旋式设计表明了优越的制冷剂分配性能.
结论:
- 在垂直头部实施螺旋结构可显著改善微通道换热器的双相流量分布.
- 这种结构修改导致更好的制冷剂分布,这对于优化热交换器性能至关重要.
- 螺旋式头部为提高制冷和空调系统效率提供了一个有前途的解决方案.
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