Bidirectional Underwater Drag Reduction on Bionic Flounder Two-Tier Structural Surfaces.

ABSTRACT: Engineering marvels found throughout the exclusive structural features of biological surfaces have given rise to the progressive development of skin friction drag reduction. However, despite many previous works reporting forward drag reduction where the bio-inspired surface features are aligned with the flow direction, it is still challenging to achieve bidirectional drag reduction for non-morphable surface structures. Inspired by the flounder ctenoid scales characterized by tilted, millimeter-sized oval fins embedded with sub-millimeter spikes, we fabricate a bionic flounder two-tier structural surface (BFTSS) that can remarkably reduce the forward skin friction drag by η_dr = 19%. Even in the backwards direction, where the flow is completely against the tilting di

SUBMITTER: He X 

PROVIDER: S-EPMC10046520 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature