Hydraulics of an Ogee Spillway with a Curved Plan: The Cade of Germichai Dam

Authors

• Sajjad Kiani
• Salah KouchakZadeh
• Seyed Ahmad Hosseini

Abstract

The Crest of an Ogee spillway with a curved plan is longer than that of one with a straight crest; therefore, its capacity for the overflow at any reservoir level is higher than that of the straight-crested spillway. Thus it is a preferred design in most water ponding projects. The objective of this study was to investigate the degree of its curvature on its hydraulics. This was a achieved on a 1:25 experimental model of the Germ chai ogee spillway at the Hydraulics Laboratory of the Soil Conservation and Water Management Research Institute of the Ministry of Jihadi Agriculture. The results revealed that the cavitation number at any discharge rate was higher than the critical value compared with that of the straight- crested weirs Moreover, the discharge coefficient was lower than that of the other type with an equal crest length.                    

Keywords

• Curve plan
• discharge coefficient
• Cavitation Number
• Pressure head

20.1001.1.20086377.1395.9.28.4.5

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