Primary study on circulation structures and vortex-scale characteristics of Huanghuacheng reach in the Three Gorges Reservoir area

Bend flow structure plays an important role in the evolution of natural river morphology. In order to further deepen the understanding of circulation structures and turbulence characteristics in the bends. Taking the continuous bend in Huanghuacheng reach of the Three Gorges Reservoir area as the research object, Acoustic Doppler Current Profiler(ADCP) was used to carry out prototype three-dimensional instantaneous velocity measurements. Scale distribution characteristics of bend circulation structures and turbulence structures were further analyzed. Results show the presence of macro-scale channel circulation structures in the Huanghuacheng reach. Due to the influence of local backwater and riverbed topography, measured vertical lines were characterized by full-depth circulation structure or double-circulation structure. Very large-scale turbulence structures still exist in the continuous curved rivers of the reservoir area, but their scale and distribution are greatly affected by the curved circulation structures.