Effect of Changes in the Hydraulic Conditions on the Velocity Distribution around a L-Shaped Spur Dike at the River Bend Using Flow-3D model

Evaluation of the characteristics and flow behavior of rivers and related structures is a complex phenomenon that makes it inevitable to use the software. Spur dike is a simple hydraulic structure which is used for rivers organization at the bends and straight paths, erosion control and protection of river banks. In this paper, flow pattern around a bunch of impermeable spur dikes with intervals specified at the bends is evaluated for various discharges and percentages of different narrowing of the flow widths; then they will be compared with each other. Also the velocity distribution around the L-shaped spur dikes is evaluated in two and three dimensions using the finite volume method. Based on the conducted experiments, maximum speed limit and thus the amount of scour has declined from the first spur dike at the angle of 30 ° to the last spur dike at the angle of 90° from the river bend and in the direction of water flow and all the turbulence of flow is lost when the flow reaches to the last spur dike.