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滴滴从一个粒子床跳跃
Karl Cardin1, Facundo Cabrera-Booman1, Raúl Bayoán Cal1
1Department of Mechanical & Materials Engineering, Portland State University, Portland, OR 97201, USA. rcal@pdx.edu.
Soft matter
|February 29, 2024
概括
在微重力实验中,从粒子床跳出滴滴. 颗粒层减少能量损失,验证了弹质量阻尼器模型的滴滴反弹动态.
科学领域:
- 流体动力学 流体动力学
- 微重力科学是一门微重力科学.
- 表面科学是一门科学.
背景情况:
- 滴滴的行为在各种工业和自然过程中至关重要.
- 了解滴滴与表面,特别是粒子床的相互作用是复杂的.
- 现有的滴滴动态模型往往需要根据特定条件进行改进.
研究的目的:
- 为了研究微重力下的粒子床中的滴滴跳动力学.
- 分析粒子层对接触线散射的影响.
- 验证和扩展一个弹质量阻尼器模型用于滴滴反弹.
主要方法:
- 使用降落塔设施进行的实验模拟微重力.
- 使用的颗粒床是由不同尺寸的聚乙烯和聚烯球体制成的.
- 系统地改变了液体粘度,Bond数 (Bo0),韦伯数 (We) 和Ohnesorge数 (Oh).
主要成果:
- 发现颗粒层显著影响滴滴跳跃行为.
- 通过存在粒子层,接触线散射被有效地消除.
- 一个经过修改的弹质量阻尼器模型准确地预测了液滴跳跃时间和速度,跨越了广泛的参数范围.
结论:
- 粒子床提供了一种方法来控制微重力过渡期间的滴滴消散.
- 经过验证的模型为滴滴反弹现象提供了一个预测工具.
- 这项研究有助于我们更好地理解减少重力环境中的界面上的流体行为.
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