Experimental study of the Impact of asymmetrical converging angle guide walls of ogee-spillway with curve axis on chute''''''''''''''''s hydraulics performance

< p >The ogee spillway with curve axis has a longer crest length. Therefore, in a specific reservoir water level, it can discharge higher flow rate compared to a straight one and due to this reason is preferred in applicable plans. In this study, the physical model of ogee spillway with curve axis was constructed of Plexiglas. The SCWMRI Soil Conservation and Watershed Management Research Institute, has led a research effort on it. This paper utilizing a three-dimensional 1:50 scale. physical model, was conducted to an investigation and compression into the hydraulics performance of chute downstream relating to crested-ogee spillway with curve axis in considering both symmetrical and asymmetrical of varying training walls convergence angles. In varying flow for each of the tested θ''''s, including 60 and 90 ̊, flow characteristics such as discharge, water surfaces, and vertical distributions of pressure in the hydraulics laboratory are measured in detail. Based on visual observation, at the toe and the end of straight portion of the spillway face, due to converging training walls in both symmetrical and asymmetrical situations, Interference streamlines occurred which led to generate a rooster tail phenomenon. It was observed that in the convergence angle of 90°, rooster tail had been witnessed up to slightly more than 118% Qd. However, it saw nearly 147% Qd in both 60° convergences. Moreover, it should be emphasized that due to asymmetric angles, closest wall to the rooster tail had more static pressure.