Understanding the wetting characteristics of a droplet on a solid surface is an important topic in basic research and various engineering applications. The further understanding of wetting characteristics of working fluid is very valuable for revealing the mechanism of phase change heat transfer, especially for understanding the complex phenomena of phase change heat transfer of mixtures. In this study, the wetting behaviors of R32, R1234yf, and R32/R1234yf nanodroplets on square pillar-type substrates were investigated by molecular dynamics simulations. The influences of structure size, droplet composition, and droplet size on the position of the critical line were investigated in particular. The results show that the droplet tends to be the Cassie state with higher pillar and shorter spacing. The influence of droplet composition on wetting state conversion is approximately linear with concentration. The influence of droplet size is relatively small. The results are reasonably explained by the force analysis method proposed in this paper.

中文翻译：

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R32，R1234yf及其混合物在柱型纳米结构基底上的润湿特性的分子动力学分析。

了解液滴在固体表面上的润湿特性是基础研究和各种工程应用中的重要主题。进一步了解工作流体的润湿特性对于揭示相变传热的机理，特别是对于理解混合物相变传热的复杂现象非常有价值。在这项研究中，通过分子动力学模拟研究了R32，R1234yf和R32 / R1234yf纳米滴在方柱型基底上的润湿行为。特别研究了结构尺寸，液滴组成和液滴尺寸对临界线位置的影响。结果表明，液滴趋于呈卡西状态，具有较高的柱子和较短的间距。液滴组成对润湿状态转化的影响与浓度近似成线性关系。液滴尺寸的影响相对较小。通过本文提出的力分析方法可以合理地解释结果。