Numerical Study of Drag Reduction on Grooved Surface

摘要

In recent decade, research on drag reduction by bionic surface technology has become a hot issue in the scope of marine engineering. Grooved surfaces is considered as the most effective method to improve the efficiency of vessel navigation. In this paper, based on the theory of computational fluid dynamics (CFD), a numerical model on the flow characteristics of the groove surface was established, which was compared with smooth surface. The results indicate that behaviors of flow field on grooved surfaces have been obviously improved. The boundary layer thickness are increased, while the velocity gradient, the shear stress and the turbulent kinetic energy are decreased. These verify the effectiveness of grooved surfaces for drag reduction. Series of groove size were introduced to further analyze on the drag reduction effect. The maximum and minimum of turbulent kinetic energy are proportion to the maximum and minimum of shear stress respectively. The narrower and deeper groove leads to higher ratio of drag reduction with the lower minimum of turbulent kinetic energy.