Author(s): Oscar Castro-Orgaz; Willi H. Hager
Keywords: Backwater curve; curvilinear flow; eddy viscosity; free overfall; turbulent flow; undular hydraulic jump
Abstract: Joseph Valentin Boussinesq (1842–1929) is known in open channel hydraulics for the outstanding theory bearing his name to deal with streamlined-flows. However, the original developments did not last over time and remain lost in his original writings. A current state of the art indicates domination of the gradually-varied flow theory in research, teaching and practice. The present Forum paper explores the original work of Boussinesq, from which it is discovered that his theory is more general than currently believed. Important findings include an original solution for the turbulent velocity profile with streamline curvature, a misleading interpretation of his famous velocity correction coefficient bearing his name, and a rigorous and systematic classification of backwater curves, including these arising from curvilinear flows. This presentation is intended to diffuse his theory to its definite inclusion in research, teaching and practice, given its superiority over current standards of gradually-varied flow computations.