Computation of Normal and Critical Depths in Parabolic Cross Sections

Abstract

With a suitable non-dimensionalization, the available charts for normal depth computation in parabolic sections are reduced to a single dimensionless curve when either Manning's or Chezy's resistance equation is used. Moreover, simple approximate solutions are presented to compute normal depth with a quite adequate degree of accuracy. Upon rearranging the critical-flow criterion equation, relevant explicit relationships are derived for this state of flow. The procedure of normal and critical depths calculation is clearly described through some examples.