Calibration of weirs using unsteady flow

This paper presents a method for unsteady calibration of rectangular and triangular weirs using height measurement instead of another flow measurement device as a standard. The theoretical equation of the dependence of the flow with the head for that weir, as long as the covered area, must be known. The method is theoretically developed and applied to a rectangular and to a triangular type of weir obtaining very good results when compared to other studies. In both cases the coefficients of discharge values were 0.617 and 0.587, respectively, which is very well within the values obtained by other researchers. In those analysis, the coefficient of determination of was as high as 0.998.