在滴滴撞击加热墙壁时,热毛细管中央叶片陷
Patrick Palmetshofer1, Anne K Geppert2, Jonas Steigerwald2
1Institute of Aerospace Thermodynamics, University of Stuttgart, 70569, Stuttgart, Germany. patrick.palmetshofer@itlr.uni-stuttgart.de.
Scientific reports
|January 11, 2024
概括
研究人员发现了一种新现象,即在水滴撞击加热表面时,一个较低薄膜厚度的状区域围绕一个被困的气泡形成. 这种效应是由热毛囊对流和马兰戈尼效应驱动的,影响流体动力学.
科学领域:
- 流体动力学 流体动力学
- 热传递是一种热传递.
- 表面科学是一门学科.
背景情况:
- 在各种工业应用中,水滴对加热表面的影响至关重要.
- 了解滴滴撞击时被困的气泡的行为是控制热量和质量转移的关键.
研究的目的:
- 通过实验观察和理论解释一个新奇的现象,即围绕被困的气泡而变薄的圆形膜.
- 为了研究滴水大小,冲击速度,表面湿透性和温度对这种现象的影响.
主要方法:
- 对高韦伯数水滴对光滑加热墙壁的影响的实验观测.
- 直接数值模拟带有封闭泡的液体薄膜.
主要成果:
- 观察到一个较低薄膜厚度的状区域在被困的气泡周围形成.
- 这种现象被解释为一个两步过程,涉及热毛细管对流和马兰戈尼效应.
- 数字模拟证实了提出的理论解释.
结论:
- 由气泡表面的温度梯度驱动的热毛囊对流会诱导流体流动.
- 马兰戈尼效应导致辐射流体加速,导致泡周围的液体自放大耗尽.
- 这种机制解释了 toroidal 稀薄区域的形成,影响加热表面上的滴滴动态.
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