Calibrating the Discharge Coefficient of Semicircular Crested Weir


This study deals with the evaluation of discharge coefficient of semicircle crested weir extending across the full width of the channel (suppressed).It is stable over flow pattern, easy to pass floating debris, and has large coefficient of discharge. Data obtained from laboratory experiments provide information on head – discharge relationship for three models with different radius of curvature.Each model has an empirical head- discharge equation. The momentum equation is applied to derive discharge per unit width. The predicted values of discharge coefficient for the proposed models based on direct discharge measurement & the derived discharge equation. The proper application of this study is an equation show that the discharge coefficient is proportional with upstream head above weir crest & inversely with the radius of curvature.