THEORETICAL AND EXPERIMENTAL STUDY OF INTERNAL WAVES GENERATED BY A DENSITY CURRENT DOWN A SLOPING BOTTOM

Internal waves of the fundamental mode propagating into a shoaling region have been studied experimentally in a continuously stratified fluid. The waves divide into three classes depending upon the ratio of the bottom slope γ to the wave-characteristic slopec. For γ/c< 1, the amplitude and wavenumber changes of the waves over the slope are in reasonable accord with a simple inviscid linear theory, prior to wave breakdown near the intersection of the slope and surface. Considerable mixing occurs in this corner region. When γ/c= 1, a striking instability of the bottom boundary layer is observed and the waves are heavily damped. When γ/c> 1, the waves are inhomogeneous and have complex spatial dependence.

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Second-mode nonlinear internal waves over a sloping bottom

Acoustical Physics ◽

10.1134/s1063771013010041 ◽

2013 ◽

Vol 59 (1) ◽

pp. 62-67 ◽

Cited By ~ 5

Author(s):

A. S. Belogortsev ◽

S. A. Rybak ◽

A. N. Serebryanyi

Keyword(s):

Internal Waves ◽

Nonlinear Internal Waves ◽

Second Mode ◽

Sloping Bottom

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Experimental Study of Ship Internal Waves—The Supersonic Case

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2920081 ◽

1993 ◽

Vol 115 (1) ◽

pp. 16-22 ◽

Cited By ~ 2

Author(s):

H. Ma ◽

M. P. Tulin

Keyword(s):

Experimental Study ◽

Internal Wave ◽

Wave Field ◽

Experimental Method ◽

Internal Waves ◽

Measured Data ◽

Density Distributions ◽

Wave Patterns ◽

Wave Profiles ◽

Theoretical Results

Internal waves produced by a ship traveling faster than the fastest internal waves (supersonic case) were investigated experimentally in our laboratory in a wide tank using averaging conductivity wave gages developed for this investigation. The wave gage is similar to the conductivity probe, but has space-averaging electrodes. An array of seven such gages was used in a wave tank with dimensions 12 ft length, 8 ft width, 2 ft depth. The water in the tank was stratified with salt to obtain desired density distributions. A spheroid, split vertically, was towed against and along a sidewall to simulate a moving ship. Simultaneous wave profiles at various distances normal to the track of the ship were obtained for different Froude numbers and density distributions. The internal wave patterns were calculated from the measured data and compared with theoretical results. The amplitude on the first crest of the internal wave field is also plotted against the distance from the ship, and a limited comparison with theory is made. The experimental method developed for this study is sensitive, simple and reliable. It may serve to obtain a data base for ship-generated internal waves under a variety of conditions.

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