EGU Vienna-2011 - Meeting

1. Numerical: GERRIS / L.E.S. comparisons GERRIS numerical code / ECM experiments comparisons GERRIS LES Experiments GERRIS numerical simulation of wind over waves moving to the shore GERRIS No wind No wind Velocity Vorticity Velocity Wind: U10=11 m/su*=50cm/s, zo=1mmlogarithmic profile Wind: U10=11 m/s,u*=50cm/s,zo=1mmlogarithmic profile Vorticity Wave shoaling U=15m/s 3 Setup U=15m/s U=6 m/s U=11m/s 2 Water level (cm) U=8m/s maxima U=0 m/s U=5m/s U=0m/s 1 U=8m/s 0 minima -12 -8 -6 -4 -2 0 2 Distance from shore (cm) Wind effects on waves propagating to the shore: experimental and numerical investigations H. Branger (1),L. Grare (1), Ch. Kharif(1,2), P. Lubin (3), S. Glockner (3), P. Robin (1,2) and O. Kimmoun (1,2) EGU Vienna-2011 - Meeting (1) branger@irphe.univ-mrs.fr - IRPHE/CNRS, Campus Luminy, Case 903, 13009 Marseille, France (2) Ecole Centrale Marseille, (ECM), 38 rue Joliot Curie, 13451 Marseille, France; (3) Laboratoire I2M/CNRS, 16 avenue Pey-Berland, 33607 Pessac Cedex, France Goal: Physical and numerical experiments on wave transformation in the surf zone and in the swash zone, with a wind blowing on-shore: wind effects on wave shoaling, wave setup and wave runup E)ECM Boussinesq numerical code (Bingham et al., Coast. Eng., 56, 2009 ; Robin et al, Journ Hydro, Nantes, 2011)+ Wind input model (Jeffreys, Proc R. Soc. Lond, 107, 1925; Miles, JFM, 3, 1957)+ Roller breaking model (Shaffer et al,Coast. Eng., 20, 1993)+ Runup model(Lynett et al, Coast. Eng., 46, 2002)Regular and Irregular (Jonswap) waves + WindSimulation of ECM and IRPHE Wind experiments A) Experimental : ECM wave tank 17m x 0.7m x0.7m, bottom slope 1/15Regular and Irregular (Jonswap) waves(Kimmoun et al, JFM, vol 588, 2007) wave gauges, PIV, Image processing run-up, setup, water elevation, phase celerity, velocities Tools: B)Experimental : IRPHEWind wave tank 40m x 2.6m x0.9m (water)x1.6m(air) bottom slope 1/30Regular and Irregular (Jonswap) waves + Wind wave gauges, Image processing, laser, anemometer run-up, setup, water elevation, celerity, wind speed D)L.E.SI2M Large Eddy Simulation numerical code, 2-phases Navier Stokes Solver, VOF method, subgrid scale turbulence model, interface tracking method(Lubin et al, EJM, 2011, doi:10.1016/j.euromechflu.2011.01.001)Regular wavesSimulation of ECM experiment C)GERRIS numerical code: open source 2-phases Navier Stokes solver , VOF Method, adaptive mesh refinement http://gfs.sourceforge.net/wiki/index.php/Main_PageRegular waves + WindSimulation of ECM + Wind experiment Results: Experiment / models (GERRIS, LES, Boussinesq) location of wave extrema (envelope) Boussinesq model / IRPHE experiments 28m from wavemaker, at depth 5cm maxima 1)Experiment/ ModelComparisons Mean water level minima Jonswap waves + Wind : 2D Map of Wave Celerity (IRPHE experiments) 2) Wind effects Wind effects on Jonswap Waves  Increase of wave celerity, run-up, wave setup, modification of dispersion relationship (Tissier et al, EJM, 2011) Wind effect on water level setup - Experiment Wind effects on extrema locations (GERRIS Numerical) Wind effect on wave shoaling (Jonswap) - Experiment Setup Water level (cm) time (s) Conclusions: Wind blowing towards the shore has a large effect on wave kinematics, shoaling, run-up and water level setup Numerical Tools under progress : dissipation, sub-grid modelisation, breaking roller and run-up parameterizations for Boussinesq model need to be improved A very thin numerical spatial discretization is required (Dx < 1mm) French ANR Grant HEXECO