Large Eddy Simulation of periodic flow characteristics at river channel confluences

This paper describes an application of Large Eddy Simulation methods to the flow in a laboratory-style confluence of parallel channels of unequal dept hs (Reynolds No. approximate to 13,500), and a natural river channel conflu ence that also exhibits pronounced bed discordance (Reynolds No approximate to 100,000) The aim is to investigate the formation of periodic flow featu res inherent in the flow dynamics in river confluences. The laboratory-styl e confluence predictions are compared with experimental data, and suggest t hat the simulation was capable of capturing some of the key flow periodicit ies. The model provides detailed flow and mixing data which help inform und erstanding of the production and evolution of large scale turbulence featur es in confluences.