Division of critical flow at three-branch open-channel intersection

作者：Abderrezzak Kamal El Kadi^*; Lewicki Leszek; Paquier Andre; Riviere Nicolas; Travin Gilbert

来源：Journal of Hydraulic Research, 2011, 49(2): 231-238.

DOI：10.1080/00221686.2011.558174

• Channel intersection
• depth-averaged model
• dividing flow
• laboratory experiment
• open channel junction
• transcritical flow

An experimental study of the characteristics of dividing critical flows in a 90 degrees open-channel junction formed by three horizontal equal-width branches is presented, conducted for various inflow discharges and downstream boundary conditions. Outflow discharges and flow depths were also measured. Four main flow patterns are identified considering the location and length of the hydraulic jumps that develop across the main and lateral channels. A relationship between the discharge division ratio and the tailwater Froude number is found, reproducing well the experimental data. Practical applications of this relationship include the design of open channel and pipe networks and one-dimensional numerical modelling of flood propagation in urban areas. The study shows also that a two-dimensional depth-averaged numerical model hardly gives better predictions of the discharge ratios because of the presence of three-dimensional features at the junction.

• 出版日期2011