水力动力合将声学上升的水晶融化
Brady Wu1,2, Bryan VanSaders1,2, Melody X Lim1,2
1Department of Physics, University of Chicago, Chicago, IL 60637.
概括
研究人员使用声波悬浮将粒子组装成可调节的格子. 他们发现,声场强度驱动了从晶体到液态的过渡,揭示了对多体系统中的水力动力学合和无热刺激的见解.
科学领域:
- 物理 物理学 物理
- 软物质物理学 软物质物理学
- 流体动力学 流体动力学
背景情况:
- 声波悬浮使研究集体粒子动力学成为可能.
- 以前的工作仅限于具有摩擦接触的2D紧密装载.
- 克服这些局限性是探索新的自组装系统的关键.
研究的目的:
- 为了克服声学悬浮中的2D密集的局限性.
- 将粒子组装成可调节的单层格子,并控制间距.
- 为了研究粘性流和水力动力学合在粒子组装中的作用.
主要方法:
- 使用空气粘度产生排斥性流动流的小颗粒.
- 调整与粘性流长度尺度相对的粒子大小,以控制力.
- 采用声波悬浮来诱导和研究低度环境中的粒子动态.
主要成果:
- 实现了颗粒组装成单层格子,具有可调节的间距.
- 证明声场强度控制自发刺激驱动重排.
- 观察到由动态异质性和间歇性特征的从晶体状态过渡到类似液体状态.
结论:
- 在空气中流动的粘性流提供了一个机制,以避免在声波悬浮中发生摩擦接触.
- 声学刺激可以以无散射的方式驱动集体粒子重新排列.
- 该研究阐明了相互作用粒子系统中水力动力学合引起的热外刺激和不稳定性.
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