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Two-dimensional stability of finite-amplitude gravity waves on water of finite depth with constant vorticity

Published online by Cambridge University Press:  03 October 2017

M. Francius*
Affiliation:
Université de Toulon, CNRS/INSU, IRD, Mediterranean Institute of Oceanography (MIO), UM 110, 83957 La Garde, France
C. Kharif
Affiliation:
Aix Marseille Université, CNRS, Centrale Marseille, IRPHE UMR 7342, 13384, Marseille, France
*
Email address for correspondence: marc.francius@mio.osupytheas.fr

Abstract

A numerical investigation of normal-mode perturbations of a two-dimensional periodic finite-amplitude gravity wave propagating on a vertically sheared current of constant vorticity is considered. For this purpose, an extension of the method developed by Rienecker & Fenton (J. Fluid Mech., vol. 104, 1981, pp. 119–137) is used for the numerical computations of the finite-amplitude waves on a linear shear current. This method enables to compute accurately waves with or without critical layers and pressure anomalies. The numerical results of the linear stability analysis extend the weakly nonlinear analytical results of Thomas et al. (Phys. Fluids, vol. 24, 2012, 127102) to fully nonlinear waves. In particular, the restabilization of the Benjamin–Feir modulational instability, whatever the depth, for an opposite shear current is confirmed. For these sideband instabilities, the numerical results show some deviations with the weakly nonlinear theory as the wave steepness of the basic wave and vorticity are increased. Besides the modulational instabilities, new instability bands corresponding to quartet and quintet instabilities, which are not sideband disturbances, are discovered. The present numerical results show that with opposite shear currents, increasing the shear reduces the growth rate of the most unstable sideband instabilities but enhances the growth rate of these quartet instabilities, which eventually dominate the Benjamin–Feir modulational instabilities.

Type
Papers
Copyright
© 2017 Cambridge University Press 

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References

Ashton, A. C. L. & Fokas, A. S. 2011 A non-local formulation of rotational water waves. J. Fluid Mech. 689, 129148.CrossRefGoogle Scholar
Baumstein, A. I. 1998 Modulation of gravity waves with shear in water. Stud. Appl. Maths 100, 365390.Google Scholar
Brevik, I. 1979 Higher-order waves propagating on constant vorticity currents in deep water. Coast. Engng 2, 237259.Google Scholar
Cheng, J., Cang, J. & Liao, S.-J. 2009 On the interaction of deep water waves and exponential shear currents. Z. Angew. Math. Phys. 60, 450478.Google Scholar
Choi, W. 2009 Nonlinear surface waves interacting with a linear shear current. Maths Comput. Simul. 80, 101110.Google Scholar
Chow, K. & Benney, D. J. 1986 Instabilities of waves on a free surface. Stud. Appl. Maths 74, 227243.Google Scholar
Cokelet, E. D. 1977 Steep gravity waves in water of uniform arbitrary depth. Phil. Trans. R. Soc. Lond. A 286, 184230.Google Scholar
Constantin, A. & Strauss, W. 2004 Exact steady periodic water waves with vorticity. Commun. Pure Appl. Maths LVII, 481527.Google Scholar
Constantin, A. & Varvaruca, E. 2011 Steady periodic water waves with constant vorticity: Regularity and local bifurcation. Arch. Rat. Mech. Math. Anal. 199, 3367.Google Scholar
Dalrymple, R. A. 1974 A finite amplitude wave on a linear shear current. J. Geophys. Res. 79, 44984504.Google Scholar
Francius, M. & Kharif, C. 2006 Three-dimensional instabilities of periodic gravity waves in shallow water. J. Fluid Mech. 561, 417437.CrossRefGoogle Scholar
Hsu, H. S., Francius, M., Montalvo, P. & Kharif, C. 2016 Gravity-capillary waves in finite depth on flows of constant vorticity. Proc. R. Soc. Lond. A 472, doi:101098/rspa.2016.0363.Google Scholar
Hur, V. M. & Johnson, M. A. 2015 Modulational instability in the whitham surface with surface tension and vorticity. Nonlinear Anal. 129, 104118.Google Scholar
Johnson, R. S. 1976 On the modulation of water waves on shear flows. Proc. R. Soc. Lond. A 347, 537546.Google Scholar
Jonsson, I. G. 1990 Wave-current interactions. In The Sea, pp. 65120. Wiley Interscience.Google Scholar
Kishida, N. & Sobey, R. J. 1988 Stokes theory for waves on linear shear current. J. Engng Mech. 114, 13171334.Google Scholar
Ko, J. & Strauss, W. 2008 Large-amplitude steady rotational water waves. Eur. J. Mech. (B/Fluids) 27, 96109.Google Scholar
Kozlov, V. & Kuznetsov, K. 2014 Dispersion equation for water waves with vorticity and stokes waves on flows with counter-currents. Arch. Rat. Mech. Math. Anal. 214, 9711018.Google Scholar
Li, J. C., Hui, W. H. & Donelan, M. A. 1987 Effects of velocity shear on the stability of surface deep water wave trains. In Nonlinear Water Waves (ed. Horikawa, K. & Maruo, H.), pp. 213220. Springer.Google Scholar
Longuet-Higgins, M. S. 1978a The instabilities of gravity waves of finite amplitude in deep water. I. Superharmonics. Proc. R. Soc. Lond. A 360, 471488.Google Scholar
Longuet-Higgins, M. S. 1978b The instabilities of gravity waves of finite amplitude in deep water. II. Subharmonics. Proc. R. Soc. Lond. A 360, 489505.Google Scholar
McLean, J. W. 1982 Instabilities of finite-amplitude gravity waves on water of finite depth. J. Fluid Mech. 114, 331341.Google Scholar
Miroshnikov, V. A. 2002 The Boussinesq–Rayleigh approximation for rotational solitary waves on shallow water with uniform vorticity. J. Fluid Mech. 456, 132.CrossRefGoogle Scholar
Moreira, R. M. & Chacaltana, T. A. 2015 Vorticity effects on nonlinear wave-current interactions in deep water. J. Fluid Mech. 778, 314334.Google Scholar
Nwogu, O. G. 2009 Interaction of finite-amplitude waves with vertically sheared current fields. J. Fluid Mech. 326, 179213.Google Scholar
Oikawa, M., Chow, K. & Benney, D. J. 1987 The propagation of nonlinear wave packets in a shear flow with a free surface. Stud. Appl. Maths 76, 6992.Google Scholar
Okamura, M. & Oikawa, M. 1989 The linear stability of finite amplitude surface waves on a linear shearing flow. J. Phys. Soc. Japan 58, 23862396.Google Scholar
Pak, O. S. & Chow, K. W. 2009 Free surface waves on shear currents with non-uniform vorticity: third order solutions. Fluid Dyn. Res. 41, 113.Google Scholar
Peregrine, D. H. 1976 Interaction of water waves and currents. Adv. Appl. Mech. 16, 9117.Google Scholar
Ribeiro, R. Jr, Milewski, P. A. & Nachbin, A. 2017 Flow strurcture beneath rotational water waves with stagnation points. J. Fluid Mech. 812, 792814.Google Scholar
Rienecker, M. M. & Fenton, J. D. 1981 A Fourier approximation method for steady water waves. J. Fluid Mech. 104, 119137.Google Scholar
Simmen, J. A. & Saffman, P. G. 1985 Steady deep-water waves on a linear shear current. Stud. Appl. Maths 73, 3557.Google Scholar
Swan, C. & James, R. L. 2001 A simple analytical model for surface water waves on a depth-varying current. Appl. Ocean Res. 22, 331347.Google Scholar
Teles da Silva, A. F. & Peregrine, D. H. 1988 Steep, steady surface waves on water of finite depth with constant vorticity. J. Fluid Mech. 195, 281302.Google Scholar
Thomas, G. P. & Klopman, G. 1997 Wave-current interactions in the near shore region. In Gravity Waves in Water of Finite Depth (ed. Hunt, J. N.), pp. 255319. WIT Press.Google Scholar
Thomas, R., Kharif, C. & Manna, M. A. 2012 A nonlinear Schrödinger equation for water waves on finite depth with constant vorticity. Phys. Fluid 24, 127102.Google Scholar
Tsao, S. 1959 Behaviour of surface waves on a linearly varying current. Mekh. Prikl. Mat. 3, 6684.Google Scholar
Vanden-Broeck, J.-M. 1996 Periodic waves with constant vorticity in water of infinite depth. IMA J. Appl. Maths 56, 207217.Google Scholar