Closure to “Minimum Specific Energy and Critical Flow Conditions in Open Channels” by Hubert Chanson

Abstract

In open channel flows, the relationship between specific energy and flow depth presents a singularity at critical flow conditions. Although the concept of critical flow was first introduced as a singularity of the backwater equation (Belanger 1828), it was associated with the idea of minimum specific energy by Bakhmeteff (1912). This approach is now commonly used (Henderson 1966, Chanson 2004) including herein. Numerous solutions of the critical flow conditions were proposed for flat channels with hydrostatic pressure distributions. Herein solutions for non-hydrostatic pressure distribution flow situations are developed, and compared with experimental measurements.