Author(s): Jiayue Hu; Hubert Chanson

Linked Author(s): Jiayue Hu

Keywords: Hydraulic jumps; Jump toe oscillations; Physical modelling; Low inflow Froude number; Free-surface turbulence; Roller dynamics

Abstract: A hydraulic jump is characterised by the sudden transition of high-velocity supercritical flow to subcritical flow in an open channel. In this study, new experiments were conducted in a large-size facility focusing with low inflow Froude numbers (2.1 < Fr1 < 3.8). Digital cameras were employed to capture the detailed free-surfaedynamics, focusing on both transverse and longitudinal characteristics of the hydraulic jump toe. This preliminary investigation captured perimeter profiles with at least 150 data points across the full width of the jump. The data revealed that the longitudinal and transverse oscillations were likely caused by three-dimensional turbulent structures in the roller and air being trapped at the impingement point. The findings contribute to a deeper understanding of the complex flow behaviour in hydraulic jumps, with implications for both theoretical studies and practical applications.

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P2079-cd

Year: 2025