An Assessment Of The Effects Of Sound Speed Fluctuations On Sound Propagation In Shallow Water Using A Perturbation Method

The physical characteristics are compared between shallow and deep water, in physics and acoustics, respectively. There is a specific sound speed profile in deep water, which is different from which in shallow water, resulting in different sound propagation law between them. In this paper, the sound field distributions are simulated under respective typical sound speed profile. The color figures of sound intensity are obtained, in which the horizontal ordinate is distance, and the vertical ordinate is depth. Then we can get some important characteristics of sound propagation. The results show that the seabed boundary is an important influence on sound propagation in shallow water, and sound propagation loss in deep water convergent zone is visibly less than which in spherical wave spreading. We can realize the remote probing using the acoustic phenomenon.

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Simulation for Range Prediction of Active Sonar in Shallow Water

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.385-386.514 ◽

2013 ◽

Vol 385-386 ◽

pp. 514-517 ◽

Cited By ~ 1

Author(s):

Liang Zhang ◽

Chun Xia Meng ◽

Jian Na

Keyword(s):

Shallow Water ◽

Sound Speed ◽

Sound Absorption ◽

Sound Propagation ◽

Propagation Characteristic ◽

Water Medium ◽

Speed Profile ◽

Long Distance ◽

Sound Speed Profile ◽

Active Sonar

In shallow water the acoustic wave from ambient noise sources carries a large number of environment information based on the complicated reflection both on the surface and seabed interface. The sound speed profile is one of the influencing factors of sound propagation characteristic, while for a long distance the sound absorption coefficient of water medium has an important significance to propagation range. The simulation results show that in shallow water sound absorption of seabed, sound speed profile and sound absorption of water were taken into account, then range prediction of active sonar can be exactly obtained using normal-mode propagation.

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SIMULATION OF UNDERWATER ACOUSTICAL FIELD FLUCTUATIONS IN SHALLOW SEA WITH RANDOM INHOMOGENEITIES OF SOUND SPEED: DEPTH-DEPENDENT ENVIRONMENT

Journal of Computational Acoustics ◽

10.1142/s0218396x14400025 ◽

2014 ◽

Vol 22 (01) ◽

pp. 1440002 ◽

Cited By ~ 5

Author(s):

OLEG E. GULIN ◽

IGOR O. YAROSHCHUK

Keyword(s):

Shallow Water ◽

Sound Speed ◽

Scientific Literature ◽

Water Layer ◽

Statistical Simulation ◽

Frequency Range ◽

Shallow Sea ◽

Field Fluctuations ◽

Pekeris Waveguide ◽

Speed Fluctuations

Statistical problems encountered in the study of the influence of random inhomogeneities in layered shallow water on the propagation of sound signal is considered. The study is carried out by the example of two-layer models of the sea — a stochastic Pekeris waveguide and a waveguide with a regular refraction in the water layer, which describes the presence of the thermocline. The results were obtained by statistical simulation without approximations and assumptions. In the middle frequency range for actual parameters of sound speed fluctuations in shallow sea with a loss penetrable bottom, the specific features of acoustic field statistical moments behavior have been discovered. They did not get adequate attention in the scientific literature.

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Analyzing sound speed fluctuations in shallow water from group-velocity versus phase-velocity data representation

The Journal of the Acoustical Society of America ◽

10.1121/1.4792354 ◽

2013 ◽

Vol 133 (4) ◽

pp. 1945-1952 ◽

Cited By ~ 7

Author(s):

Philippe Roux ◽

W. A. Kuperman ◽

Bruce D. Cornuelle ◽

Florian Aulanier ◽

W. S. Hodgkiss ◽

...

Keyword(s):

Phase Velocity ◽

Shallow Water ◽

Group Velocity ◽

Sound Speed ◽

Data Representation ◽

Velocity Versus ◽

Velocity Data ◽

Versus Phase ◽

Speed Fluctuations

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Effect of Guide’s Acoustic Parameters on Vertical Directivity of the Marine Ambient Noise

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.577.1207 ◽

2014 ◽

Vol 577 ◽

pp. 1207-1210

Author(s):

Chun Xia Meng ◽

Hao Mu ◽

Gui Juan Li

Keyword(s):

Shallow Water ◽

Sound Speed ◽

Ambient Noise ◽

Sound Propagation ◽

Sea Water ◽

Surface Boundary ◽

Ray Theory ◽

Directivity Characteristic ◽

Acoustic Parameters ◽

Equipment Performance

The vertical directivity characteristic of ambient noise is one inherent characteristic of the ocean in shallow water. And it includes the information of guide’s acoustic characteristic information. The marine guide is composed of sea water; seabed and surface boundary, there into, the acoustic parameters of seabed are hardly obtained exactly. In this paper, the model of vertical directivity for ambient noise is established. Based on the ray theory of sound propagation, the influence of guide’s acoustic parameters which include sound speed, density and attenuation coefficient on vertical directivity of marine ambient noise is simulated. The results are propitious to analysis and command the characteristics of ambient noise, and valuable to accelerate the exertion of acoustic equipment performance.

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Sound speed fluctuations and signal coherence in very shallow water: experimental description

IEEE Oceanic Engineering Society. OCEANS'98. Conference Proceedings (Cat. No.98CH36259) ◽

10.1109/oceans.1998.725740 ◽

2002 ◽

Author(s):

O. Bergem ◽

N.G. Pace

Keyword(s):

Shallow Water ◽

Sound Speed ◽

Speed Fluctuations

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Influences Analysis of Environmental Parameters on Sound Propagation in Shallow Water

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.4815 ◽

2014 ◽

Vol 556-562 ◽

pp. 4815-4819

Author(s):

Shahabuddin Shaikh ◽

Yi Wang Huang

Keyword(s):

Shallow Water ◽

Sound Speed ◽

Sound Propagation ◽

Transmission Loss ◽

Water Environment ◽

Environmental Parameters ◽

Sea Surface ◽

Water Medium ◽

Sea Bottom ◽

Shallow Water Environment

The objectives of this paper are to analyze the effectiveness of parameters on sound propagation in a shallow-water environment. The procedure for calculation of transmission loss is only the method to analyze the influence of environmental parameters. The normal mode approach is carried out for the calculation of transmission loss. And it is conducted in the range independent environment Transmission loss for sound propagation in shallow water depends upon many natural variables such as sea surface, water medium, and sea bottom. Analyses are finalized on the results obtained by considering two types of sound channels. The results indicated that acoustic transmission loss in a shallow-water environment is dependent on the source & receiver depths, sea surface, sound speed profile (SSP) in water, sound speed in bottom, density of water & bottom, propagation range and frequency. It is necessary to mention that better transmission was found during the sound velocity increases with depth; whereas the poor transmission occurred in negative gradient channel.

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