Author(s): Matthias Kramer

Linked Author(s): Matthias Kramer

Keywords: Stepped spillway; Velocity profile; Mixing-Layer; Log-law

Abstract: Velocity distributions in supercritical open-channel flows down stepped chutes are typically described using a power-law approach, which is suitable for velocity profiles above step edges. In between step edges, theoretical solutions of plane turbulent mixing layers have successfully been compared with measurements, but no generalized model is available to date. In this study, a four-layer velocity model is proposed, which is able to characterize flow velocities above the pseudo-bottom as well as within the step cavities. This new model combines different physical concepts (mixing layer, log-layer, wake function) and was validated against previous experimental data, recorded in the developing non-aerated region of a stepped chute. It is anticipated that the model is also applicable within aerated flow regions, which is yet to be disclosed through detailed velocity measurements in challenging two-phase conditions, especially inside step cavities.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022820

Year: 2022