流量模式研究和压力下降预测,在不同表面可浸透性微通道的双相沸过程
Yuqi Zhang1, Haoxian Wu1, Ling Zhang2,3
1School of Physics, Sun Yat-sen University, Guangzhou 510006, China.
Micromachines
|May 27, 2023
概括
改变微通道表面的湿透性可以增强热传递,减少双相流动过程中的压力下降. 表面的湿度,质量流和蒸汽质量显著影响双相摩擦压力下降.
科学领域:
- 热传递热量转移的方法
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 微通道中的双相流量对于紧型换热器至关重要.
- 表面湿度显著影响流动模式和压力下降.
- 现有的模型在预测微通道中的二相流动行为时往往缺乏准确性.
研究的目的:
- 实验研究表面湿度对微通道双相流量压力下降的影响.
- 在不同的条件下分析泡行为和流动模式.
- 开发一种新的相关性来预测二相摩擦压力下降.
主要方法:
- 在微通道中对R-134a双相流的实验研究,具有超性,性和常见表面.
- 不同的质量流量 (713-1629 kg/m2s) 和热流量 (7.0-35.1 kW/m2).
- 分析泡行为,流动模式,压力下降,并开发新的相关性.
主要成果:
- 水友的表面修饰有效地增强了热传递,并减少了摩擦压力下降.
- 质量流量,蒸汽质量和表面湿透性是影响压力下降的关键参数.
- 开发了一个新的"流量顺序度"参数和相关性,显示超友微通道的平均绝对误差为19.8%.
结论:
- 表面湿度是优化微通道中双相流量性能的一个关键因素.
- 与以前的模型相比,拟议的相关性为预测压力下降提供了更好的准确性.
- 水友的表面改造为增强热管理系统提供了一个可行的策略.
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