在流体驱动的颗粒流中形成虫洞
Miles L Morgan1, David W James1, Martin Monloubou2
1Complex Fluids Research Group, Department of Chemical Engineering, Swansea University, Swansea, UK.
Communications physics
|November 27, 2025
概括
通过密集的颗粒物质流动的流体可以创建类似虫洞的通道,绕过散装材料. 当引力驱动的流动不能供应流体辅助区域时,这种不稳定性就会出现,从而影响工业和自然过程.
科学领域:
- 地质物理学 地质物理学
- 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:
- 流体驱动的颗粒流表现出复杂的行为和不稳定性.
- 纵向流体通过密集的沉积粒流动并未得到充分理解.
- Silo 流动力学在各种工业和自然环境中至关重要.
研究的目的:
- 为了研究一个沉浸在水中的液体驱动筒仓的行为,其中有密集的沉积粒.
- 识别和描述新出现的不稳定性和流动模式.
- 开发流体-颗粒相互作用的预测模型.
主要方法:
- 对一个水下流体驱动筒仓的实验研究.
- 观察不同的流动模式,包括指纹,多孔流和通道形成.
- 开发经验模型来预测不稳定的开始.
主要成果:
- 观察到多样化的行为:指纹,多孔流,经典的筒子流和类似虫洞的通道.
- 虫洞通道迅速传播到出口,绕过主要的颗粒包装.
- 不稳定的开始与流体辅助区域的不足引力驱动供应有关.
结论:
- 虫洞通道的形成是流体驱动的密集颗粒流中的关键不稳定性.
- 一个模型平衡流量组件预测基于谷粒大小和流速的通道出现.
- 研究结果为在自然灾害和工业过程中管理流体-颗粒相互作用提供了一个框架.
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