Study on surface fabrication and drag reduction performance of the bionic fish-scale composite structure

Abstract

It has been researched that the surface structure of many organisms has unique resistance reduction properties and it is important to replicate the morphological features of the biological body surface on the material surface. So, a method for creating a biomimetic fish-scale surface using a laser is proposed by observing the laminar arrangement features of three common fish scales on the body surface, and a composite structure of bionic fish scale macrostructure and different microstructures of bionic fish scale were machined on on aluminium alloy surfaces. The surface morphology and elemental composition were characterized before the resistance reduction test. The results indicate that both the biomimetic fish-scale macrostructure and composite structure have an obvious effect of reduced drag, among which, maximum resistance reduction can be achieved 44.02% at a flow rate of 0.6 m/s for the bionic carp fish scale composite structure.