国际空间站的包装床反应堆实验:气液双相流中的毛细管效应
Mahsa Taghavi1, Brian J Motil2, Henry Nahra2
1Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA. mtaghav2@central.uh.edu.
NPJ microgravity
|July 18, 2023
概括
国际空间站的实验揭示了气体液体包装床的不同流动模式. 压力下降取决于流量历史,并为每个系统提供相关性.
科学领域:
- 流体动力学 流体动力学
- 微重力科学是一门微重力科学.
背景情况:
- 了解包装床中的双相气液流对于工业过程至关重要.
- 像国际空间站 (ISS) 这样的微重力环境提供了独特的条件来研究这些流动,不受地球的重力影响.
研究的目的:
- 为了分析两相气液流体在微重力中通过一个装载床的流动模式和压力下降的实验数据.
- 确定流量模式过渡边界,并开发压力下降相关性.
主要方法:
- 在国际空间站 (ISS) 上获得的实验数据的分析.
- 通过分析压力梯度与流量相比,识别流动模式 (分散泡,脉冲,延长/大泡,气体连续).
- 对于每个已识别的流量模式,压力下降 (摩擦因子) 相对关系的发展.
主要成果:
- 观察了四种不同的流动模式,并确定了它们的过渡边界.
- 发现压力下降是流量历史的函数,表现出hysteresis.
- 歇斯底里相对的大小随着气体或液体流速的增加而减少.
- 毛细管/界面对压力梯度的贡献在气体通道系统中占主导地位,与大气泡系统中的粘性贡献相比.
- 初步数据显示,在大气泡状态下,气体积累缓慢,行为间歇.
结论:
- 微重力包装床的流量模式和压力下降是复杂的,并受到流量历史的影响.
- 开发出来的相关性为预测不同流量模式下的压力下降提供了基础.
- 需要进一步调查大气泡制度中的气体积累和间歇现象.
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