Lateral mixing in a meandering open channel flow

A large eddy simulation of flow in a periodic meandering open channel with a rectangular cross-section is presented. The Reynolds number based on the channel height is 40.000 and the aspect ratio of the cross-section is 4.48. Furthermore, the transport and mixing of a passive scalar is analysed using three different positions of release, e.g. on the inner bank, on the outer bank and on the center of the cross section. The obtained depth-average concentration profiles show good agreement with available experimental data. The role of the secondary motions in the mixing processes is the main focus of the discussion.