School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
Langmuir. 2011 Dec 6;27(23):14143-50. doi: 10.1021/la200816f. Epub 2011 Nov 11.
The prevention and control of ice accumulation has important applications in aviation, building construction, and energy conversion devices. One area of active research concerns the use of superhydrophobic surfaces for preventing ice formation. The present work develops a physics-based modeling framework to predict ice formation on cooled superhydrophobic surfaces resulting from the impact of supercooled water droplets. This modeling approach analyzes the multiple phenomena influencing ice formation on superhydrophobic surfaces through the development of submodels describing droplet impact dynamics, heat transfer, and heterogeneous ice nucleation. These models are then integrated together to achieve a comprehensive understanding of ice formation upon impact of liquid droplets at freezing conditions. The accuracy of this model is validated by its successful prediction of the experimental findings that demonstrate that superhydrophobic surfaces can fully prevent the freezing of impacting water droplets down to surface temperatures of as low as -20 to -25 °C. The model can be used to study the influence of surface morphology, surface chemistry, and fluid and thermal properties on dynamic ice formation and identify parameters critical to achieving icephobic surfaces. The framework of the present work is the first detailed modeling tool developed for the design and analysis of surfaces for various ice prevention/reduction strategies.
积冰的防治在航空、建筑施工和能源转换装置等领域具有重要应用。一个活跃的研究领域涉及使用超疏水表面来防止冰的形成。本工作开发了一个基于物理的建模框架，用于预测由于过冷水滴撞击而导致冷却的超疏水表面上的冰形成。该建模方法通过开发描述液滴冲击动力学、传热和非均相成核的子模型，分析了影响超疏水表面上冰形成的多种现象。然后将这些模型集成在一起，以全面了解在冻结条件下液滴撞击时的冰形成。该模型通过成功预测实验结果得到验证，实验结果表明，超疏水表面可以完全防止低至-20 至-25°C 的表面温度下冲击水的冻结。该模型可用于研究表面形态、表面化学、流体和热特性对动态冰形成的影响，并确定实现冰阻表面的关键参数。本工作的框架是为各种防冰/减冰策略的表面设计和分析开发的第一个详细建模工具。
