Energy Dissipation Potentials of Grouped Spur Dikes in an Open Channel

Spur dikes are frequently preferred flow regulation structures, especially for open channels and coastal morphology due to their ease of application and economics. Since spur dikes placed on the edge of the stream isolated (single) or in groups do not have a length across the entire channel width, they can also play the role of a semi-permeable weir in the stream. In this study, the effects of spur dikes of the same length and height placed asymmetrically on both sides of the channels at five different angles on the flow were investigated experimentally and numerically. The energy dissipation ratios of the spur dikes in the channel were calculated in submerged and unsubmerged flow conditions. A total of 45 tests were performed using nine different discharges, and comparisons were made by transferring the same characteristics from the experimental conditions to the numerical environment. According to the obtained data, the situation with the highest energy dissipation occurred at θ = 120°. At low discharges, more vortex was observed in the eyes between the dikes, but as the discharge increased, the vortex seen in the flow decreased. The velocity distributions on the channel cross-sections were also presented to obtain flow patterns along disturbed flow in the channel. At the maximum discharge, the θ = 30° placement showed the highest velocities in most cross-sections, while the lowest velocities were observed at the θ = 120°.