Influence of wing scales of Catocala electa Borkhason on the frosting process

Abstract

The frosting processes on the wing surface before and after removing the scale of the Catocala electa Borkhauson were observed by using a self-assembled experiment device. The results showed that the formation process of frosting on the wing surface with or without scales was similar. However, the scale could affect the attachment shape of water vapour on the wing surface and the time when frost began to form. The formation time of frosting on the wing surface without scales was earlier than that on the wing surface with scales, which was about 614 s. The influence mechanism of the scales on the frosting process was analyzed from the wettability and morphology of the scales on the wing surface Catocala electa Borkhauson. The scale on the wing surface of Catocala electa Borkhauson showed superhydrophobic properties, and the scale surface had criss-cross ribs, which formed many special micro-nano spaces. Superhydrophobicity could promote the rolling of water on the scales and reduce the adhesion area between water and scale surface. The special space structure could delay the cooling of droplets on the scale surface of Catocala electa Borkhauson. The study might be helpful to design or optimize the functional surfaces with anti-frosting properties based on the structure of the scale surface.

Keywords

• catocala electa borkhauson
• wing scales
• frosting
• superhydrophobic
• microstructure