Review of Flow Hydrodynamics and Sediment Transport at Open Channel Confluences

Abstract

Confluences are common occurrences along the natural rivers as well as artificial open channels. A confluence is characterized by the presence of a stagnation zone, a separation zone, a mixing layer and the recovered flow in the downstream. The bed erosion occurs because of turbulence at the confluence. The eroded soil at the confluence poses problems by deposition in the downstream locations such as check dams, barrages, and reservoirs if not controlled, resulting in reduction of water storage capacity as well as water quality. Recently, the number of studies on the confluences have increased, however, link between flow hydrodynamics and sediment transport, bed morphology at the confluence is still incompletely understood. In this paper, earlier studies on open channel confluences are discussed to summarize flow hydrodynamics and sediment transport phenomenon.

Three‐dimensional turbulent structures at a medium‐sized confluence with and without an ice cover

“…Conceptual models of confluence dynamics derived from these experiments often depict the mixing layer as a relatively narrow zone (e.g. figure in Shakibainia et al ., , Schindfessel et al ., , Chen et al ., ; Wuppukondur, ), with minor importance compared to the separation zone at the downstream junction corner. There is an overall paucity of conceptual models based on field research that have investigated the turbulent flow dynamics of confluences.…”