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Journal of Marine Science and Application 2015年第4期14卷 413-424页

作者： Parviz Ghadimi Alireza Bolghasi Mohammad A. Feizi Chekab Rahim Zamanian Department of Marine Technology Amirkabir University of Technology Tehran 15875-4413 Iran International Campus-Mechanical Engineering Group Amirkabir University of Technology Tehran 15875-4413 Iran

The main goal of this paper is to investigate sound scattering from the sea surface, by Kuo＇s small perturbation method （SPM）, in the Persian Gulf＇s environmental conditions. Accordingly the SPM method is reviewed, then it is demonstrated how it can accurately model sound scattering from the sea surface. Since in Kuo＇s approach, the effects of surface roughness and sub-surface bubble plumes on incident sounds can be studied separately, it is possible to investigate the importance of each mechanism in various scattering regimes. To conduct this study, wind and wave information reported by Arzanah station as well as some numerical atmospheric models for the Persian Gulf are presented and applied to examine sound scattering from the sea surface in the Persian Gulf region. Plots of scattering strength by Kuo＇s SPM method versus grazing angle for various frequencies, wave heights, and wind speeds are presented. The calculated scattering strength by the SPM method for various frequencies and wind speeds are compared against the results of critical sea tests 7 （CST-7）. The favorable agreement achieved for sound scattering in the Persian Gulf region is indicative of the fact that the SPM method can quite accurately model and predict sound scattering from the sea surface.

关键词： sea surface Persian Gulf small perturbation method (SPM) wind rose plots wave rose plots sound scattering surface roughness sub-surface bubble plumes

Ocean circumstance effects on the sound scattering of thermocline

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Chinese Journal of Acoustics 1995年第1期14卷 11-18页

作者： BAO Qinghua (Ocean University of Qingdao, Qingdao 266003)

This paper is based on the proven statement that sound scattering in shallow sea de pends mainly on thermocline, and is to analyze the contribution from sound scattering by plankton, and the effects of waves and other parameters of oceanic condition, on fluctuations of travelling time and amplitude of received signals. The results showed that the effect of plankton density distribution only appeared as a background interference. And main component of in terference is come from wind wave and swell.

关键词： Ocean circumstance sound scattering Thermocline

Sea Surface Effects on sound scattering in the Persian Gulf Region Based on Empirical Relations

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Journal of Marine Science and Application 2015年第2期14卷 113-125页

作者： Parviz Ghadimi Alireza Bolghasi Mohammad A. Feizi Chekab Department of Marine Technology Amirkabir University of Technology Tehran 15875-4413 Iran

In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.

关键词： surface scattering strength scattered intensity seasurface effects Persian Gulf sound scattering empirical relation perturbation theory

Acoustic radiation force on a multilayered sphere in a Gaussian standing field

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Chinese Physics B 2018年第3期27卷 299-305页

作者： Haibin Wang Xiaozhou Liu Sha Gao Jun Cui Jiehui Liu Aijun He Gutian Zhang Key Laboratory of Modern Acoustics Institute of AcousticsNanjing UniversityNanjing 210093China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China Nanjing Drum Tower Hospital The Affiliated Hospital of Nanjing University Medical SchoolNanjing 210093China

We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering *** expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid,The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed,with particular emphasis on the shell thickness of every layer,and the width of the Gaussian *** results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka,as well as the shell thickness of each *** study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave,which may benefit the improvement and development of acoustic control technology,such as trapping,sorting,and assembling a cell,and drug delivery applications.

关键词： acoustic radiation force Gaussian standing field multilayered sphere model sound scattering

Development of a New Target Simulator

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International Journal of Plant Engineering and Management 1999年第1期4卷 404-410页

作者： Gao Tiande Li Zhishun(College of Marine Engineering, Northwestern Polytechnical UniversityXi’an, 710072, Shaanxi, P.R.China)

*** of a general target simulator are too few to provide the sonar equipmentand sonar signal-Processing algorithm with a set of integrated experimental data. In this paper anew universal target simulator is developed based on the sound scattering theory. It can produceintegrated simulated data for the various existing sonar equipment and the usual sonar signalprocessing algorithms. The means and efficiency of detection of sonar equipment are improvedby this new simulator In the meantime, this new device stimulates the research on sonar signalprocessing algorithms.

关键词： target simulator sonar equipment sound scattering DSP (Digital SignalProcessing)