中国物理B ›› 2011, Vol. 20 ›› Issue (7): 74301-074301.doi: 10.1088/1674-1056/20/7/074301

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

The diffracted sound field from the transition region of an axisymmetric body in water

黎雪刚, 杨坤德, 汪勇   

  1. College of Marine, Northwestern Polytechnical University, Xi'an 710072, China
  • 收稿日期:2011-01-18 修回日期:2011-03-01 出版日期:2011-07-15 发布日期:2011-07-15

The diffracted sound field from the transition region of an axisymmetric body in water

Li Xue-Gang(黎雪刚)†, Yang Kun-De(杨坤德), Wang Yong(汪勇)   

  1. College of Marine, Northwestern Polytechnical University, Xi'an 710072, China
  • Received:2011-01-18 Revised:2011-03-01 Online:2011-07-15 Published:2011-07-15

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摘要： Understanding the physical features of the diffracted sound field on the surface of an axisymmetric body is important for predicting the self-noise of a sonar mounted on an underwater platform. The diffracted sound field from the transition region of an axisymmetric body was calculated by the geometrical theory of diffraction. The diffraction ray between the source point and the receiving point on the surface of an axisymmetric body was calculated by using the dynamic programming method. Based on the diffracted sound field, a simulation scheme for the noise correlation of the conformal array was presented. It was shown that the normalized pressure of the diffracted sound field from the transition region reduced with the increases of the frequency and the curvature of the ray. The flow noises of two models were compared and a rather optimum fore-body geometric shape was given. Furthermore, it was shown that the correlation of the flow noise in the low frequencies was stronger than that in the high frequencies. And the flow noise received by the acoustic array on the curved surface had a stronger correlation than that on the head plane at the designed center frequency, which is important for sonar system design.

Abstract: Understanding the physical features of the diffracted sound field on the surface of an axisymmetric body is important for predicting the self-noise of a sonar mounted on an underwater platform. The diffracted sound field from the transition region of an axisymmetric body was calculated by the geometrical theory of diffraction. The diffraction ray between the source point and the receiving point on the surface of an axisymmetric body was calculated by using the dynamic programming method. Based on the diffracted sound field, a simulation scheme for the noise correlation of the conformal array was presented. It was shown that the normalized pressure of the diffracted sound field from the transition region reduced with the increases of the frequency and the curvature of the ray. The flow noises of two models were compared and a rather optimum fore-body geometric shape was given. Furthermore, it was shown that the correlation of the flow noise in the low frequencies was stronger than that in the high frequencies. And the flow noise received by the acoustic array on the curved surface had a stronger correlation than that on the head plane at the designed center frequency, which is important for sonar system design.

Key words: diffracted sound field, flow noise, uniform geometric theory of diffraction, correlation

中图分类号:  (Noise in water; generation mechanisms and characteristics of the field)

  • 43.30.Nb
43.30.Lz (Underwater applications of nonlinear acoustics; explosions)