The mechanism of drag reduction performance depending on the secretion rate of biomimetic mucus for a bio-inspired surface

Abstract In order to better suppress the turbulent burst phenomenon on the surface of the underwater vehicle and improve the drag reduction efficiency of the bionic surface, in this paper, based on the turbulent boundary layer theory, a hydrodynamic model is constructed, and the strip structure and vortex structure of mucus with different secretion rates are obtained by simulation, and the comparative analysis is carried out respectively. The results show that when 1/um+ is 2, the bionic mucus is evenly distributed on the wall, and the strips number near the wall is the lowest and the intertwining degree is the lowest; the flow direction vortices have the lowest number and density, and the mucus pore vortices do not lead to the increased of drag. The research in this paper improves the drag reduction efficiency of the bionic surface to 36.79%, which provides a theoretical basis for the selection of the biomimetic mucus secretion rate in the drag reduction applications of underwater vehicles.