Dual-coupling drag reduction inspired by tuna skin: Fan-shaped imbricated fish scale composited with flexible coating

Fluid Drag Reduction with Shark - Skin Riblet Inspired

Inspired by designs found throughout living nature, researchers are reverse engineering the world’s fl ora and fauna to solve technical challenges. Much attention is given to structures and materials since living nature effi ciently uses resources and incorporates ingenious designs to survive. Therefore by using lessons from living nature, bioinspired designs are serving as the basis for many n...

Turbulent Drag Reduction by Spanwise Wall Oscillations

The objective of this paper is to examine the effectiveness of wall oscillation as a control scheme of drag reduction. Two flow configurations are considered: constant flow rate and constant mean pressure gradient. The Navier-Stokes equations are solved using Fourier-Chebyshev spectral methods and the oscillation in sinusoidal form is enforced on the walls through boundary conditions for the sp...

Analysis of elasmoid fish imbricated layered scale-tissue systems and their bio-inspired analogues at finite strains and bending†

We examine deformation mechanisms and performance of multilayered structures inspired by imbricated scale-tissue systems of elasmoid fish. Exact analytical solutions are derived for these soft composite structures undergoing finite deformation in compressive and bending loading conditions. The layered structure leads to dramatic coupled shear-compressive deformations which afford distinct and a...

otection by design: imbricated hybrid microstructures of bio-inspired armor

Drag reduction by riblets.

The interaction of the overlying turbulent flow with riblets, and its impact on their drag reduction properties are analysed. In the so-called viscous regime of vanishing riblet spacing, the drag reduction is proportional to the riblet size, but for larger riblets the proportionality breaks down, and the drag reduction eventually becomes an increase. It is found that the groove cross section A(...