在量子流中解温度和雷诺斯数效应
Juan Ignacio Polanco1,2, Philippe-E Roche3, Luminita Danaila4
1CNRS, Ecole Centrale de Lyon, Institut National des Sciences Appliquées de Lyon, Universite Claude Bernard Lyon 1, Laboratoire de Mécanique des Fluides et d'Acoustique, UMR 5509, Ecully 69130, France.
概括
超流体4He中的量子流涉及粘性和摩擦消散. 相互摩擦有助于能量级联,但仍然是最小的,允许新的雷诺兹数定义,解释旋间距和间歇性.
科学领域:
- 流体动力学 流体动力学
- 量子力学就是量子力学.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 了解超流体4He中的量子流需要分析粘性和摩擦散射.
- 霍尔-维宁-贝哈雷维奇-哈拉特尼科夫 (HVBK) 模型描述了正常流体和超流体组件之间的相互摩擦.
研究的目的:
- 为了获得量子流的逐级能源预算.
- 调查相互摩擦在能量消散和级联动力学中的作用.
- 为了定义一个有效的雷诺兹数对两流体流,并澄清温度和雷诺兹数对间歇性的影响.
主要方法:
- 开发了一种粗粒度的双流体模型.
- 推导出一个逐个规模的能源预算.
- 在HVBK模型框架内执行直接的数值模拟 (DNS).
- 分析了实验和数值数据.
主要成果:
- 相互摩擦促进了流体之间的动量交换和联合能量级联,尽管粘度不同.
- 摩擦消散很小,并且在远消散尺度上局部化.
- 定义了一个有效的雷诺兹数,用于两流体流.
- 建立了正常化的旋间距和雷诺兹数之间的关系,得到了数据的支持.
- 间歇性变化归因于雷诺兹数效应,而不是温度变化.
结论:
- 这项研究阐明了量子流中粘性和摩擦消散的相互作用.
- 定义的有效雷诺兹数为分析两流体流提供了一个新的工具.
- 这些发现解决了关于间歇性的辩论,将其归因于雷诺兹数效应.
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