Turbulent structure and bursting process in multi-bend meander channel

The flow characteristics in a meander channel are fully three-dimensional. With the primary flow in the streamwise direction, the secondary flow in the transverse and vertical directions induced by the channel bends are significant in the analyses of the turbulent structure. Some of the analyses in the straight channel, for instance, the quadrant analysis for the bursting phenomena, are inadequate in investigating the meander channel, since the flow in the transverse direction is not taken into account. In order to reveal the flow characteristics in a multi-bend meander channel, especially, the bursting process, experiments are conducted in the present study. With the three-dimensional quadrant analysis, the influence of the transverse flow velocity during the bursting process could be correctly addressed. The analyses and discussions are presented in this paper.