Laboratory investigations on hydraulic jump characteristics using submerged vanes and adverse slope

Abstract

Hydraulic jumpis a phenomenon with destructive effects on the river bed and downstream the hydraulic structures. This study, based on experimental findings, presents a new method that can be used to prevent the detrimental impacts of the hydraulic jump downstream of hydraulic structures and to design optimal structures. In this empirical research, 135 experiments were conducted in an experimental flume where submerged vanes with angles of attack of 30 and 60°, as a novel intuitive method, were used with two different configurations and adverse slopes (0, −1.5% and −3%) to control hydraulic jump in the range of 4.58 < Fr1 < 9.14. Based on the obtained results, the sequent depth and length of the hydraulic jump were, at most, decreased by 26.6% and 31.9%, respectively, with increasing the angle of attack of submerged vanes and the adverse slope of the bed. Also, the energy loss increased up to 7.7% in the case of φ = 60°, d = 0.2 m, and S = −3%. To calculate the sequent depth and length of the hydraulic jump, new equations were expressed through the analysis of the effects associated with the angle of attack, adverse slope, and vane configuration. All data resulting from proposed equations were then compared and validated with the experimental data.