Evaluation the influence of aerator ramp on reducing the cavitations risks in Shafaroud Azad and Gotvand dams

Current weather indifferent fields of science and engineering research purposes and different applications are studied. One of the applications of climate studies, the study of the flow over the weir dam and lower exhaust tunnel is aimed at preventing the risk of cavitations. Aeration is known as one of the most economical and practical way to deal with cavitations on rapid spill ways. In the study of the phenomena of cavitations and aeration systems, three dams on Iran to prevent this phenomenon from a physical model including dam spillway such as Shafaroud, Azad and Gotvand are investigated. According to the result sofa single Shafaroud dam spillway, aeration system has little effect on reducing the risk of cavitations. In the Azad dam spillway, using two aeration systems as the first option, and in the Gotvand dam spillway, using three aeration systems as the first and second choices in both channels was the best options of aeration. According to the conducted studies by comparing the performance of aerator ramp in Azad and Gotvand dams led to acceptable results. Thus, in comparing the performance of aeration systems of these two spillway dams, we can say with lower (values of height to horizontal length ratio of the ramp (a/b), the maximum horizontal length of jet from the aerator ramp, chute angle and the height difference between the beginning and end of the spillway) and higher (height and horizontal length of the aerator ramp), the aeration efficiency will be the best.