Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-26T06:58:00.504Z Has data issue: false hasContentIssue false

A generalized stability criterion for resonant triad interactions

Published online by Cambridge University Press:  26 April 2006

Carson C. Chow
Affiliation:
NeuroMuscular Research Center, Boston University, Boston, MA 02215, USA
Diane Henderson
Affiliation:
Department of Mathematics, Penn State University, University Park, PA 16802, USA
Harvey Segur
Affiliation:
Program in Applied Mathematics, University of Colorado, Boulder, CO 80309–0526, USA

Abstract

It is well known that in any conservative system that admits resonant triad interactions, a uniform (test) wavetrain that participates in a single triad is unstable if it has the highest frequency in the triad, and neutrally stable otherwise. We show that this result changes significantly in the presence of coupled triads: with coupling, the test wave can be unstable to a high-frequency perturbation. The coupling sends energy from the (weak) high-frequency source into particular low-frequency waves that grow even though they had zero amplitudes initially. This mechanism thereby selects these low-frequency waves from the spectrum of low-frequency waves available for triad interactions. Moreover, the instability persists in the presence of weak damping, provided the wave amplitudes exceed two thresholds. First, the initial amplitude of the test wavetrain must be large enough for the instability to dominate the damping. Secondly, the (small) initial amplitudes of the high-frequency perturbations must exceed a threshold in order for the low-frequency waves to grow to a prescribed amplitude.

Type
Research Article
Copyright
© 1996 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bers, A. 1972 Linear waves and instabilities. In Plasma Physics - Les Houches (ed. C. De Witt & J. Peyraud), pp. 117215. Gordon and Breach, New York, 1975).
Craik, A. D. D. 1984 Wave Interactions and Fluid Flows. Cambridge University Press.
Hammack, J. L. & Henderson, D. M. 1993 Resonant interactions among surface water waves. Ann. Rev. Fluid Mech. 25, 5597.Google Scholar
Harper, P. G. & Wherrett, B. S. 1975 Nonlinear Optics. Academic Press.
Hasselmann, K. 1967 A criterion for nonlinear wave stability. J. Fluid Mech. 30, 737739.Google Scholar
Henderson, D. & Hammack, J. 1987 Experiments on ripple instabilities. Part 1. Resonant triads. J. Fluid Mech. 184, 1541.Google Scholar
Louisell, W. H. 1960 Coupled Mode and Parametric Electronics. Wiley.
McEwan, A. D. 1971 Degeneration of resonantly-excited standing internal waves. J. Fluid Mech. 50, 431448.Google Scholar
McGoldrick, L. F. 1965 Resonant interactions among capillary-gravity waves. J. Fluid Mech. 21, 305331.Google Scholar
Manley, J. M. & Rowe, H. E. 1956 Some general properties of nonlinear elements - Part 1. General energy relations. Proc. I.R.E. 44, 904913.Google Scholar
Miles, J. W. 1984 On damped resonant interactions. J. Phys. Oceanogr. 14, 16771678.Google Scholar
Neshyba, S. & Sobey, E. J. C. 1975 Vertical cross coherence and cross bispectra between internal waves measured in a multiple-layered ocean. J. Geophys. Res. 80, 11521162.Google Scholar
Perlin, M. & Hammack, J. 1991 Experiments on ripple instabilities. Part 3. Resonant quarters of the Benjamin-Feir type. J. Fluid Mech. 229, 229268.Google Scholar
Perlin, M., Henderson, D. & Hammack, J. 1990 Experiments on ripple instabilities. Part 2. Selective amplification of resonant triads. J. Fluid Mech. 219, 5190.Google Scholar
Simmons, W. F. 1969 A variational method for weak resonant interactions. Proc. R. Soc. Lond. A 309, 551575.Google Scholar
Tsytovich, V. N. 1970 Nonlinear Effects in Plasma. Trans. from Russian by J. S. Wood. Plenum Press.
Zakharov, V. E. 1968 Stability of periodic waves of finite amplitude on the surface of a deep fluid. J. Appl. Mech. Tech. Phys. 9, 190194.Google Scholar