颗粒状流的随机动力学:一个配置模式控制了堵塞的稳定性
David Hathcock1, Sam Dillavou2, Jesse M Hanlan2
1IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, USA.
Physical review. E
|March 19, 2025
概括
一个新的模型解释了排水器中的颗粒流,统一了临时和永久的堵塞. 它揭示了一个隐藏模式控制堵塞稳定性,改善了对流动动态和堵塞现象的理解.
科学领域:
- 物理 物理学 物理
- 工程 工程师 工程师 工程师
- 复杂的系统复杂的系统.
背景情况:
- 小出口排水器中的颗粒式流量显示了人们不太了解的行为,如临时和永久的堵塞,以及非高斯流量率统计数据.
- 之前的研究已经独立地检查了这些现象,缺乏一个统一的模型来解释流的所有方面.
研究的目的:
- 引入一个统一的现象学模型,用于解释临时堵塞,永久堵塞和非高斯流速统计.
- 提供一个动态机制,将流量与控制堵塞稳定的隐藏模式联系起来.
主要方法:
- 开发了一种基于兰格温动态的现象学模型,具有乘数噪声和零流量时的吸收状态.
- 条件在隐藏模式上的流速动态影响了堵塞稳定性.
- 分析了一个大型实验数据集 (>40000个流量) 来验证模型的预测.
主要成果:
- 该模型成功地从实验数据中复制了暂停和堵塞事件的统计数据.
- 观察到非指数分布的堵塞时间和非高斯流速分布,与模型一致.
- 解释了随着出口尺寸的增加而平均堵塞时间的伸展指数增长.
- 确定了微观的配置特征,如形结构大小和光滑度,作为隐藏模式的物理基础.
结论:
- 引入了一个统一的动态框架,以了解塞现象.
- 该模型提供了一种机制,用于将流量与隐藏变量合起来,以控制堵塞稳定性.
- 为复杂的颗粒流系统提出了新的研究方向.
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