Li Rao, Zhu Pengzhe, Yin Zhihua, Xu Yimeng
School of Mechanical Engineering, Beijing Institute of Technology, Beijing 10081, P. R. China.
Langmuir. 2022 Jun 7;38(22):7058-7066. doi: 10.1021/acs.langmuir.2c00770. Epub 2022 May 24.
The dynamic behavior of droplets impacting on textured surfaces has an important influence on many engineering applications, such as anti-icing and self-cleaning. However, the mechanism and law of the effect of textured surfaces on the impact behavior of nanodroplets has not been fully revealed yet. In this paper, the molecular dynamics (MD) method is used to model the dynamic behavior of nanodroplets after impacting the solid surface with a striped texture. The influences of texture gap and texture angle on the real contact area, spreading factor, contact time, and bounce velocity of the droplet after impact are also quantitatively analyzed. It is shown that the striped texture produces significant anisotropy in the spreading and contraction behavior of nanodroplets after impact, and the anisotropy is more pronounced on the ridged texture surface than on the grooved texture surface. In addition, we find that the texture gap has little effect on the dynamic behavior of nanodroplets impacting the textured surface. However, as the bottom angle of the texture increases, the real contact area and bounce velocity of the nanodroplet increase significantly, while the contact time and spreading factor decrease. This work further elucidates the characteristics and mechanisms of nanodroplets impacting on stripe-textured surfaces and provides a theoretical basis for the design of nanostructured surfaces in relevant applications.
液滴撞击纹理表面的动力学行为对许多工程应用具有重要影响，如防冰和自清洁。然而，纹理表面对纳米液滴撞击行为的影响机制和规律尚未完全揭示。本文采用分子动力学（MD）方法对纳米液滴撞击具有条纹纹理的固体表面后的动力学行为进行建模。还定量分析了纹理间隙和纹理角度对液滴撞击后实际接触面积、铺展因子、接触时间和反弹速度的影响。结果表明，条纹纹理在纳米液滴撞击后的铺展和收缩行为中产生显著的各向异性，且在脊状纹理表面上的各向异性比在沟槽纹理表面上更明显。此外，我们发现纹理间隙对纳米液滴撞击纹理表面的动力学行为影响很小。然而，随着纹理底部角度的增加，纳米液滴的实际接触面积和反弹速度显著增加，而接触时间和铺展因子减小。这项工作进一步阐明了纳米液滴撞击条纹纹理表面的特性和机制，并为相关应用中纳米结构表面的设计提供了理论依据。
