结在一滴撞击冷基底:树突不能透的地方?
Mingyue Ding1, Yuheng Shang2, Maria Rosaria Vetrano2
1Institute for Fluid Mechanics and Aerodynamics, Technical University of Darmstadt, Peter-Grünberg-Straße 10, Darmstadt, 64287, Germany.
Journal of colloid and interface science
|July 17, 2025
概括
超冷水滴结在寒冷的表面形成冰不同基于层厚. 当液体层比冰层厚时,树突形成,影响冰的预测.
科学领域:
- 流体物理学 流体物理学
- 材料科学 材料科学 材料科学
- 航空航天工程 航空航天工程
背景情况:
- 超冷水滴 (SLD) 在寒冷表面积累的冰在航空和基础设施方面存在重大挑战.
- SLD的结行为,特别是树突冰结构的形成和随后的回流冰,尚未完全理解.
- 现有的假设表明,冰和液体层的相对厚度会影响结模式.
研究的目的:
- 为了研究超冷水滴撞击冷表面的结动力学.
- 确定决定树突性冰结构与非树突性冰层形成的关键因素.
- 开发一个冰积累现象的预测模型.
主要方法:
- 使用高速成像观察室温和超冷水滴在冷基板上的结.
- 实验在基质温度低至-35°C和超冷滴的-10°C进行.
- 一个风洞被用来控制在冷室中的超冷滴的冲击速度.
主要成果:
- 他们发现了三种不同的结模式:树的传播,薄冰层的扩张和反向结.
- 开发了一种一维的热传导模型,其中包含了取决于温度的热特性.
- 确定了一个关键的门:当超冷的液体层比传播的冰层更厚时,树突冰的形成发生.
结论:
- 该研究成功地解释了基于冰和液体层相对厚度的观察到的结模式.
- 来自热传导模型的理论预测与实验数据保持一致.
- 这些发现为结动态提供了关键的见解,对改善航空航天应用中的冰预测模型有直接影响.
相关概念视频
Frost Action on Concrete
151
Concrete structures in cold climates, such as those along roadsides, can retain moisture. This moisture makes them susceptible to frost-related damage when temperatures fall below freezing. Adding moisture worsens the damage during temperature fluctuations, leading to repeated freezing and thawing. De-icing salts, spread over these structures to melt ice, add to the freeze-thaw cycle, and draw even more moisture into the concrete.
This freeze-thaw cycle primarily causes surface scaling, where...
This freeze-thaw cycle primarily causes surface scaling, where...
151
Phase Transitions: Melting and Freezing
13.2K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
13.2K
Theories of Dissolution: The Danckwerts' Model and Interfacial Barrier Model
446
Various dissolution theories provide insight into the factors that influence the dissolution rate. Danckwerts' Model suggests that turbulence, rather than a stagnant layer, characterizes the dissolution medium at the solid-liquid interface. In this model, the agitated solvent contains macroscopic packets that move to the interface via eddy currents, facilitating the absorption and delivery of the drug to the bulk solution. The regular replenishment of solvent packets maintains the...
446
Phase Transitions: Sublimation and Deposition
18.0K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
18.0K
Colloidal precipitates
769
The high insolubility of some precipitates can result in an unfavorable relative supersaturation. This can lead to colloidal particles with a large surface-to-mass ratio, where adsorption is promoted. For instance, in the precipitation of silver chloride, silver ions are adsorbed on the surface of the colloidal particles, forming a primary layer. This layer attracts ions of opposite charge (such as nitrate ions), forming a diffuse secondary layer of adsorbed ions. This electric double layer...
769
Freezing Point Depression and Boiling Point Elevation
35.8K
Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
35.8K


