Author(s): Adrien Momplot; Gislain Lipeme Kouyi; Emmanuel Mignot; Nicolas Rivière; Jean-Luc Bertrand-Krajewski
Keywords: Bifurcation; hydraulic experiments; hydraulic parameters; open-channel flow; RANS model; recirculation structures
Abstract: This paper aims at describing two different recirculation structures observed both numerically and experimentally in the lateral branch of a dividing open channel flow with identical downstream weirs. The flow conditions leading to each identified recirculation structure are also investigated. The first recirculation pattern is a classic two-dimensional closed recirculation, typically described in the literature. The second one is a three-dimensional helix-shaped recirculation that differs from the first one notably regarding the streamline behaviour. We show that the occurrence of each structure of recirculation can be predicted by means of the Froude number and the aspect ratio in the upstream channel of the bifurcation.