%0 Conference Proceedings %T Periodic saltation under extreme tidal currents: an experimental study %+ Lab-STICC_ENSTAB_CID_PRASYS %+ Pôle STIC_OSM %+ Adaptation et diversité en milieu marin (AD2M) %A Minster, Gaspard %A Floc'H, France %A Valance, Alexandre %A Dantec, Nicolas Le %A Nicolle, Amandine %A Filipot, Jean-François %A Zerr, Benoit %< avec comité de lecture %( Coastal Dynamics 2017Paper No. 058 %B Coastal Dynamics %C Copenhague, Denmark %8 2017-06-12 %D 2017 %K Saltation %K hydrodynamics %K Experimental modelling %K Shields number %K Restitution coefficient %K High Stokes number %Z Physics [physics] %Z Sciences of the Universe [physics]/Ocean, AtmosphereConference papers %X In extreme tidal environment and specifically in the Alderney race (English Channel, France), the ambition to install hydrokinetic turbines requires knowledge on the pebbles concentration in the water column. Some evidences of the presence of such coarse sediments at one meter above the bed have been found. An experimental study is realizedin a free surface flume for high Stokes number. With fast camera the trajectories of hundreds of spherical particles are analyzed. This study focuses on the characterization of the critical Shields number to intermittent and saltation regime and on the coefficient of restitution between the impact and the rebound velocity . The critical Shields numberis identified experimentally at 0.2. The restitution coefficient shows little dependence on the impact angle. Finally, the experimental maximum height reached by the spherical particles proves that lift and inertia forces are not negligible. %G English %L hal-01698481 %U https://ensta-bretagne.hal.science/hal-01698481 %~ UNIV-BREST %~ INSTITUT-TELECOM %~ ENSTA-BRETAGNE %~ UPMC %~ CNRS %~ UNIV-UBS %~ ENSTA-BRETAGNE-STIC %~ GIP-BE %~ ADMM %~ ENIB %~ LAB-STICC %~ UPMC_POLE_3 %~ SORBONNE-UNIVERSITE %~ SU-SCIENCES %~ SU-SCI %~ INSTITUTS-TELECOM %~ ALLIANCE-SU %~ TEST3-HALCNRS %~ TEST4-HALCNRS %~ SBR %~ TEST5-HALCNRS