在同质冷却颗粒气体中的旋转和转移运动
Torsten Trittel1,2, Dmitry Puzyrev2,3, Kirsten Harth1,2
1Department of Engineering, Brandenburg University of Applied Sciences, Magdeburger Str. 50, Brandenburg an der Havel, 14770, Germany.
NPJ microgravity
|July 31, 2024
概括
微重力中的颗粒气体实验揭示了配分违规,旋转能量为转化能量的2/3 . 观察到颗粒冷却,动能在激发后显著下降.
科学领域:
- 物理 物理学 物理
- 颗粒物质科学 颗粒物质科学
- 流体动力学 流体动力学
背景情况:
- 颗粒状材料表现出与气体或液体不同的复杂行为.
- 了解颗粒系统中的能量均分和散射对于各种应用至关重要.
研究的目的:
- 在微重力下研究颗粒气体中的能量均分.
- 描述颗粒冷却过程及其动态.
主要方法:
- 使用降落塔进行微重力实验.
- 光学视频分析以提取粒子转移和旋转.
- 在长时间内观察颗粒冷却.
主要成果:
- 违反配分:旋转自由度被激发到转化自由度的2/3左右.
- 观察到颗粒冷却,动能降低到初始值的5%.
- 对于转移和旋转自由度的可比冷却速率.
- 在冷却开始时,速度元件的高斯分布的偏差.
结论:
- 微重力条件突出了颗粒气体动态的根本差异.
- 观察到的颗粒冷却过程在不同自由度之间是一致的.
- 需要进一步的研究才能充分理解非高斯速率分布.
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