Complex flows in rivers

Kelvin-Helmholtz instabilities in shallow shear flows

Problematic issue The aim is to understand what are the  conditions of emergence  and development of Kelvin-Helmholtz-type coherent structures (KHCSs) in shallow shear flows for three types of geometries: an open-channel with a rectangular section a  composite open channel (rectangular section with a lateral variation in bed roughness) a compound open-channel (main channel + adjacent …

Laterally confined flows through macro-roughness elements

Problematic issue The aim is to study the influence of emerged or slightly submerged macro-roughness elements (modelling trees or houses in floodplains) on the structure of laterally confined flows (open-channel with a  single rectangular cross-section). Scientific issues Variation of the flow structure with the submergence parameter D/h of the macro-roughness elements (D = time-averaged water …

Overbank flows or compound open-channel flows

Problematic issue The aim is to study the hydrodynamic complexity of overflowing river flows, which are also called flows in a compound open-channel, consisting of a main channel and adjacent floodplains. Since 2014, research has focused on the impact of floodplain land use on extreme flood flows, particularly in the context of the ANR FlowRes …

Transverse and longitudinal waves in steady flows

Problematic issue The aim is to study the transverse and longitudinal free surface waves (seiche or seiching phenomenon) induced by vortex shedding behind emerged  or slightly immersed macro-roughnesses in laterally confined flows. Macro-roughnesses represent tree or house models. Scientific issues Quantification of the seiche phenomenon (transverse and longitudinal oscillations of the free surface)  for emerged …