Study on Instabilities of Two-Phase He II/vapor flow in a pipe

管道内两相He II/蒸气流不稳定性研究

• 批准号: 12450074
• 负责人: KAMIJO Kenjiro
• 金额: $ 9.6万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450074/
• 关键词: superfluid helium; multiphase flow; flow instability; liquid helium; cavitation model; drift-flux model; 極低温混相流; 極低温気液二相流; 多流体モデル

The aim of this research is to analyze the flow instability of multi-phase flow of liquid helium which consists of superfluid, normalfluid and vapor phase.The experimental apparatus for the generation of multiphase flow of superfluid helium is improved. It is important to shield the superfliud helium from the heat for high accuracy measurement. To protect the liquid helium from the outside heat the copper shield is added to the upstream and downstream tank and around the test section. Using this improved apparatus, the two-phase flow of superfluid helium is generated at the test section and the data of the relation between Reynolds number and cavitation number are obtained. For this reason, it is confirmed that the cavitation number is decreased as the Reynolds number is increased.Moreover, the phenomena are analyzed by the numerical method. The two-phase flow is assumed as bubble cavitation and the governing equations are constructed so that continuum equation, momentum equation and energy conservation is satisfied. These equations are solved by SMAC method and the flow structure at the nozzle is analyzed. Consequently, at the blowdown, the pressure decreases immediately and vortex is generated downstream of the throat.

本研究的目的是分析液氦多相流的流动不稳定性，并改进了超流氦多相流实验装置。对超流氦进行热屏蔽是高精度测量的重要条件。为了保护液氦不受外部热量的影响，在上游和下游罐以及试验段周围增加了铜屏蔽。利用改进后的装置在实验段产生了超流氦两相流，得到了雷诺数与空化数的关系数据。结果表明，空化数随雷诺数的增加而减小，并对这一现象进行了数值分析。将两相流假设为气泡空化，建立了满足连续方程、动量方程和能量守恒的控制方程。采用SMAC方法对方程组进行了求解，分析了喷管内的流动结构。因此，在泄放时，压力立即降低，并在喉部下游产生涡流。

项目成果

石本淳, 上條謙二郎: "液体ヘリウムのベンチュリ流路内キャビテーション流れに関する数値シミュレーション"低温工学. 37. 565-572 (2002)

Jun Ishimoto、Kenjiro Kamijo：“液氦文丘里通道中空化流的数值模拟”《低温工程》37. 565-572 (2002)。

Oike,M., et al.: "Two-Dimensional Numerical Simulation of Boiling Two-Phase Flow of Liquid Nitrogen"Transactions of JSASS. 43・141. 115-121 (2000)

Oike, M., et al.：“液氮沸腾两相流的二维数值模拟”，JSASS 43・141（2000）。

Ishimoto, J., Oike, M., Kamijo, K.: "Numerical Analysis of Two-Phase Pipe Flow of Liquid Helium Using Multi-Fluid Model"Transaction of ASME Journal of Fluid Engineering. 123. 811-818 (2001)

Ishimoto, J.、Oike, M.、Kamijo, K.：“使用多流体模型对液氦两相管流进行数值分析”ASME 流体工程期刊汇刊。

Ishimoto, J., Oike, M., Kamijo, K.: "Numerical Simulation of Cavitating Flow of Liquid Helium in a Pipe Using Multi-Fluid Model"Advances in Cryogenic Engineering. Vol.47. 1413-1420 (2002)

Ishimoto, J.、Oike, M.、Kamijo, K.：“使用多流体模型对管道中液氦空化流进行数值模拟”低温工程进展。

Ishimoto, J.: "Numerical Analysis of Two-Phase Pipe Flow of Liquid Helium Using Multi-Fluid Model"Journal of Fluids Engineering. Vol.123. 811-818 (2001)

Ishimoto, J.：“使用多流体模型对液氦两相管流进行数值分析”流体工程杂志。