Écoulement de surface
In collaboration with the LHE and its team, work in this field uses small wave and current flumes with new non-intrusive technologies to measure velocity at a high resolution (3D PIV, rapid PIV, ADV, ADVP, Echo-Doppler imagery). Research focuses on complex flow configurations (recirculation, bifurcation, detachment/reattachment of boundary layer, turbulence, vortex). The measurements are used to develop and run CFD codes.
Sheer stress induced by flow at the water–sediment boundary will destabilize the sediment by creating waves (wrinkles, dunes) in non-cohesive sediments (sand, gravel) or current/density rolls (mud, landslide) in cohesive sediments (clay loam). The goal of these studies is to gain knowledge of sediment transport laws (erosion, sedimentation, suspension, thrust, consolidation). These laws and their parameters are used for predictive models of the morphodynamics of rivers, estuaries, or coastal zones.
Hydraulic structures like bridges, pontoons, breakwaters, dams, or wind turbines at sea are affected by sediment transport. Work in this field examines three-way interactions between flows, structures, and sediments. Particular attention is given to jets, undertow currents, and horseshoe and Von Karman vortices, all of which can produce effects very different from classical erosion configurations.
Soil porosity plays a role in many phenomena or processes (infiltration, exfiltration, pumping), and in some cases porous flow can be detrimental to structures such as dams or dikes, breakwaters, or natural structures like shores. Work in this field focuses on flow and transport in porous environments with respect to issues such as geothermal energy production, freezing/thawing, internal erosion (supercooling, clogging, cavity and hole formation), and soil decontamination. Laminar and inertial flow regime mixing properties are of particular interest. The measurements are used to develop and run CFD codes.
The study of soil mechanical resistance is important because soil is used both as a construction material and to support structures. Compression or compression/extension cycles induced by seismic waves can increase interstitial water pressure and generate liquefaction. Work in this field will make use of the new triaxial system developed by the CT Scan Lab team in collaboration with the L3SR laboratory in Grenoble (CNRS, France).