Numerical investigation of Radius of Curvature on Flow Pattern around a Submerged T-shaped Spur Dike

Spur dike is one of the various hydraulic structures used in rivers، and are utilized in order to protect river banks، keeping the flow away from the walls، and directing them towards the main route. Due to flow digression، a turbulent circulation zone appears around the spur dike. Consequently، in order to prevent local scour، they use a wider، T-shaped nose for the spur dike. In this paper، a study on flow pattern around a 25 percent submerged T-shaped spur dike، located in a 45 degree position، in a 90 degree bend with rigid bed، and various relative radius of curvature 2، 3، 4، and 5، with a constant discharge of 25 lit/s has been conducted using Flow-3D software. Numerical results have been compared with experimental results، and they have been analyzed. The results indicate that with an increase in radius of curvature، the number of vortexes in cross sections near the wing of the spur dike، as well as lateral velocity of the flow increases، and the maximum lateral velocity is found upstream of the wing of the T-shaped spur dike. It was also observed that the less the relative radius of curvature is، the wider zone downstream of the spur dike has relative immobility of the flow.