Numerical simulation of hydraulic characteristics of an upstream wing submerged T-shaped groyne

Abstract

Groynes can prevent erosion of banks. In this study, an upstream wing submerged T-shaped groyne (ST) was proposed. The hydraulic characteristics and the bed elevation of the proposed groyne were compared with those of a T-shaped groyne. Under the consideration of the flow field measurements of a 60° bend movable bed experiment, a digital terrain after the bed development was obtained, using laser scanning technology. The flow field numerical simulation was performed with this digital terrain as the boundary. The results demonstrated that in comparison with the T-shaped groyne, the depth-averaged velocity of ST near the groyne head decreased by 14%, the length of the back-flow zone behind the ST was shortened by about 36%, and the streamlines near the wing of the groyne were smoother. Additionally, the scour depth in the range of the groyne increased by about 0.2 times the approaching flow depth H.