惯性诱导非球体大气粒子强烈的方向波动
T Bhowmick1,2, J Seesing1, K Gustavsson3
1Max Planck Institute for Dynamics and Self-Organization, Göttingen, D-37077 Germany.
Physical review letters
|February 2, 2024
概括
空气中的粒子方向显示了由于惯性而导致的衰变振荡,与液体中的单调放松不同. 这一发现对于准确建模诸如火山灰等大气粒子至关重要.
科学领域:
- 大气科学 大气科学
- 流体动力学 流体动力学
- 粒子物理学 粒子物理学
背景情况:
- 大气粒子的方向 (例如,火山灰,冰晶) 影响它们在大气中的停留时间和辐射特性.
- 了解粒子行为对于气候和大气建模至关重要.
研究的目的:
- 实验性地研究沉重的非球形粒子在不同介质中沉的方向动态.
- 从理论上解释基于物理原理观察到的定向行为.
主要方法:
- 在静止的空气和液体中沉的亚毫米球形体的实验演示.
- 理论分析包括粒子惯性和质量密度比.
主要成果:
- 沉重的亚毫米球体在静止空气中沉降时表现出衰变的方向振荡.
- 相比之下,在液体中沉时,颗粒的方向会单调地放松.
- 空气中的振荡归因于粒子惯性,由高粒子-流体质量密度比驱动.
结论:
- 粒子惯性显著影响气体介质中密集粒子的方向动态.
- 观察到的振荡行为必须纳入大气固体粒子模型.
- 对大气粒子方向的准确建模对于了解气候影响至关重要.
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