Large scale experimental study of wave-current interactions in the presence of a 3D bathymetry
Rey, V.; Touboul, J.; Guinot, F. (2012). Large scale experimental study of wave-current interactions in the presence of a 3D bathymetry, in: Rizzuto, E. et al. (Ed.) (2011). Sustainable maritime transportation and exploitation of sea resources. pp. 873-880 In: Rizzuto, E.; Soares, C.G. (Ed.) (2011). Sustainable maritime transportation and exploitation of sea resources. CRC Press: [s.l.]. ISBN 9780415620819 . 1162 pp., more |
| Authors | | Top | - Rey, V.
- Touboul, J.
- Guinot, F.
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| Abstract | Experiments were carried out in the Ocean Engineering Basin (BGO) FIRST, France, of useful length 24 metres and effective width 16 metres. A tridimensional bathymetry consisting of two symmetrical submerged mounds of maximum extension 8.5 m lengthwise was displayed on the flat bed on both sides of the basin. The maximum water depth was of 3 m, the water depth above the top of the mounds was of 1.5 m. Regular waves of frequency corresponding to either deep water or finite water depth above the bathymetry were generated without current and with either following or opposite currents. For the tests of current only, acceleration is observed above the mound over the whole basin width. A decrease of the near surface current intensity is observed downstream not only due to the increase of water depth but also to a vertical mixing. This vertical mixing is the stronger for opposite current conditions, due to higher turbulence generated through the perforated beach. In the presence of current, the mixing is enhanced, particularly for the longest waves. For opposite current conditions, a strong tridimensional behavior is observed for the amplitude. For the longest waves, transversal modes are excited by the current due to the geometry of the basin. For the shortest waves (deep water conditions), a strong focusing of the energy is observed. Indeed, amplitude of twice the incoming wave amplitude is observed in the central part (channel) of the basin. It cannot be ascribed to an increase of the current intensity since this latter is found to be almost uniform in the basin in spite of the tridimensional geometry of the mound. |
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