Dimensionless Curves for Normal-Depth Calculations in Canal Sections

Normal depth is an important parameter for the design of irrigation canals. Direct analytical solution of normal depth is not possible because of the implicit nature of governing equations. The solution usually requires tedious techniques of trial and error. Tabular and graphical methods are only available for more common cross sections. This problem has been previously addressed for some cross sections (i.e., rectangular, triangular, trapezoidal, and circular) and the calculation of normal depth in these cross sections has been reported in the literature. Reported herein are graphical solutions for normal depth in other cross sections (i.e., round-bottomed triangular, parabolic, and round-corner rectangular).