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水滴蒸发在不同的重力和电场中
M J Gibbons1, A I Garivalis2, S M O'Shaughnessy3
1Department of Mechanical, Manufacturing & Biomedical Engineering, Trinity College Dublin, the University of Dublin, Dublin 2, Ireland. Michael.Gibbons@tcd.ie.
NPJ microgravity
|May 7, 2024
概括
引力显著影响水滴蒸发,影响热量流和蒸发速度. 较大的水滴表现出更大的热惯性,而在测试条件下,电场在测试条件下没有显著影响.
科学领域:
- 流体动力学 流体动力学
- 热传递是一种热传递.
- 材料科学是一种材料科学.
背景情况:
- 滴蒸发在各种工业和科学应用中至关重要.
- 了解外部场对滴滴行为的影响对于流程优化至关重要.
研究的目的:
- 实验性地研究不同重力和电场对静态水滴蒸发的影响.
- 分析热流分布,滴滴力学和形状的影响.
主要方法:
- 在欧洲航天局 (ESA) 抛物线飞行运动 (PFC 66) 期间进行的实验.
- 测试了带有钉钉接触线的静止水滴,一致的湿透性,以及各种体积和基板热流.
- 在不同的引力条件下测量热流分布,滴状和蒸发速率.
主要成果:
- 在滴滴接触线上始终观察到峰值热传递.
- 蒸发速度,峰值热量流和平均热量流随着重力而有显著变化.
- 超重力条件显示较高的值,而微重力条件导致较低的值.
- 较大的水滴表明热惯性增加,需要更多的时间来达到热平衡.
- 没有发现电场对液滴蒸发的显著影响.
结论:
- 引力是影响静态水滴蒸发动力学和热传递的一个主要因素.
- 滴滴大小和热惯性在蒸发行为中起着至关重要的作用,特别是在短暂的条件下.
- 在测试参数下,电场不会显著改变水滴蒸发.
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