Mercier, Matthieu J.; Mathur, Manikandan; Gostiaux, Louis; Gerkema, Theo; Magalhães, Jorge M.; Da Silva, José C. B.; Dauxois, Thierry Soliton generation by internal tidal beams impinging on a pycnocline: laboratory experiments. (English) Zbl 1246.76007 J. Fluid Mech. 704, 37-60 (2012). Summary: In this paper, we present the first laboratory experiments that show the generation of internal solitary waves by the impingement of a quasi-two-dimensional internal wave beam on a pycnocline. These experiments were inspired by observations of internal solitary waves in the deep ocean from synthetic aperture radar (SAR) imagery, where this so-called mechanism of ‘local generation’ was argued to be at work, here in the form of internal tidal beams hitting the thermocline. Nonlinear processes involved here are found to be of two kinds. First, we observe the generation of a mean flow and higher harmonics at the location where the principal beam reflects from the surface and pycnocline; their characteristics are examined using particle image velocimetry (PIV) measurements. Second, we observe internal solitary waves that appear in the pycnocline, detected with ultrasonic probes; they are further characterized by a bulge in the frequency spectrum, distinct from the higher harmonics. Finally, the relevance of our results for understanding ocean observations is discussed. Cited in 6 Documents MSC: 76-05 Experimental work for problems pertaining to fluid mechanics 76B55 Internal waves for incompressible inviscid fluids 76B25 Solitary waves for incompressible inviscid fluids 76U05 General theory of rotating fluids 86A05 Hydrology, hydrography, oceanography Keywords:internal waves; ocean processes; solitary waves PDF BibTeX XML Cite \textit{M. J. Mercier} et al., J. Fluid Mech. 704, 37--60 (2012; Zbl 1246.76007) Full Text: DOI References: [1] DOI: 10.1175/1520-0485(1998)028<1853:NROIWA>2.0.CO;2 · doi:10.1175/1520-0485(1998)028<1853:NROIWA>2.0.CO;2 [2] DOI: 10.1017/S0022112007008786 · Zbl 1151.76399 · doi:10.1017/S0022112007008786 [3] DOI: 10.1017/S0022112004002769 · Zbl 1065.76034 · doi:10.1017/S0022112004002769 [4] DOI: 10.1017/S0022112003003902 · Zbl 1057.76010 · doi:10.1017/S0022112003003902 [5] DOI: 10.1016/0198-0149(92)90045-U · doi:10.1016/0198-0149(92)90045-U [6] DOI: 10.1016/0198-0149(90)90022-N · doi:10.1016/0198-0149(90)90022-N [7] DOI: 10.1016/S0967-0637(01)00082-6 · doi:10.1016/S0967-0637(01)00082-6 [8] DOI: 10.1007/s003480050064 · doi:10.1007/s003480050064 [9] DOI: 10.1017/S0022112010002454 · Zbl 1197.76041 · doi:10.1017/S0022112010002454 [10] DOI: 10.5194/npg-15-233-2008 · doi:10.5194/npg-15-233-2008 [11] DOI: 10.1017/S0022112009991236 · Zbl 1183.76636 · doi:10.1017/S0022112009991236 [12] LeBlond, Waves in the Ocean (1978) [13] DOI: 10.1357/002224001762882646 · doi:10.1357/002224001762882646 [14] DOI: 10.1063/1.3253692 · Zbl 1183.76283 · doi:10.1063/1.3253692 [15] DOI: 10.1357/0022240963213574 · doi:10.1357/0022240963213574 [16] DOI: 10.1103/PhysRevLett.102.124502 · doi:10.1103/PhysRevLett.102.124502 [17] DOI: 10.1007/s003480070003 · doi:10.1007/s003480070003 [18] DOI: 10.1029/2007JC004220 · doi:10.1029/2007JC004220 [19] DOI: 10.1017/S0022112075001516 · doi:10.1017/S0022112075001516 [20] DOI: 10.1017/S0022112001003536 · Zbl 1008.76005 · doi:10.1017/S0022112001003536 [21] DOI: 10.1017/jfm.2011.61 · Zbl 1241.76101 · doi:10.1017/jfm.2011.61 [22] DOI: 10.1016/j.dsr.2010.12.003 · doi:10.1016/j.dsr.2010.12.003 [23] DOI: 10.1007/s00348-006-0225-7 · doi:10.1007/s00348-006-0225-7 [24] DOI: 10.1029/2008JC005125 · doi:10.1029/2008JC005125 [25] DOI: 10.1063/1.2472511 · Zbl 1146.76396 · doi:10.1063/1.2472511 [26] DOI: 10.5589/m07-041 · doi:10.5589/m07-041 [27] DOI: 10.1016/j.dsr.2006.01.013 · doi:10.1016/j.dsr.2006.01.013 [28] DOI: 10.1017/S0022112072000837 · Zbl 0247.76095 · doi:10.1017/S0022112072000837 This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. It attempts to reflect the references listed in the original paper as accurately as possible without claiming the completeness or perfect precision of the matching.