Double-roughness surfaces can be used to mimic lotus surfaces. The apparent contact angles (ACAs) of droplets on these surfaces were first calculated by Herminghaus. Then Patankar utilized the pillar model to improve the Herminghaus approach and put forward the formulas for ACAs calculation of the homogeneous double-roughness surfaces where the dual-scale structures and the bases were the same wettable materials. In this paper, we propose a numerical calculation method of ACAs on the heterogeneous double-roughness surfaces where the dual-scale structures and the bases are made of different wettable materials. This numerical calculation method has successfully enhanced the Herminghaus approach. It is promising to become a novel design approach of heterogeneous superhydrophobic surfaces, which are frequently applied in technical fields of self-cleaning, anti-icing, antifogging, and enhancing condensation heat transfer.

中文翻译：

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非均质双粗糙度表面上视在接触角的数值计算方法

双粗糙度表面可用于模拟莲花形表面。这些表面上的液滴的表观接触角（ACA）首先由Herminghaus计算。然后，Patankar利用支柱模型对Herminghaus方法进行了改进，并提出了双尺度结构和基体为相同可湿性材料的均匀双粗糙度表面的ACA计算公式。在本文中，我们提出了一种在双尺度结构和基底由不同的可润湿材料制成的非均质双粗糙度表面上的ACA数值计算方法。这种数值计算方法成功地增强了Herminghaus方法。有望成为一种异质超疏水表面的新颖设计方法，