摘要
应用射线理论对收发合置深海海底混响强度进行建模。数值仿真发现,海底声吸收衰减对混响强度有较大影响,而观测点深度几乎不改变混响强度的衰减规律。当海底声吸收系数较小时,由于晚到声线传输因子的逐渐增大而使得总混响强度出现起伏。特征声线的掠射角越大,则其越晚到达散射体。随着水平距离的增大,其掠射角越晚趋于临界角,故由它们组成的闭合路径的混响对总混响起作用的水平距离也逐渐增大。
Monostatic bottom reverberation in the deep ocean is modeled based on ray theory. Numerical results show that the acoustic absorption in bottom takes large effect on the reverberation attenuation, while the observation depth doesn't affect the intensity. When the absorption coefficient is relatively small or the wave frequency is low enough, the reverberation intensity fluctuates due to the gradual contribution of the later arrivals in long range. The bigger the grazing angle is, the later the eigenray arrives. And its grazing angle tends to the internal reflection angle lately with the increase of the horizontal range. Thus the closed-path reverberation of the ray takes effect on the total reverberation at larger horizontal ranges.
引文
[1]Bucker H P,Morris HE.Normal-Mode Reverberation in Channels or Ducts[J].J.Acoust.Soc.Am.,1968;44(3):827-828.
[2]D.D.Ellis.Normal-mode models OGOPOGO and NOGRP applied to the 2006 ONR Reverberation Modeling Workshop problems[P].Technical Memorandum TM 2006-289,DRDC Atlantic,Dartmouth,NS,Canada,June 2008.
[3]H.Weinberg.Generic sonar model[P].Oceans 82,Washington,DC,USA,1982.
[4]吴金荣,孙辉,黄益旺.浅海近程混响衰[J].哈尔滨工程大学学学报,2002;23(6):4-8.Wu J R,Sun H,Huang Y W.Short Range Reverberation Intensity Decaying in Shallow Water[J].Journal of Harbin Engineering University,2002;23(6):4-8.
[5]张明辉.海底声散射强度测量方法及不规则海域混响特性的研究[D].哈尔滨:哈尔滨工程大学,2011.40-43.Zhang M H.Research on Bottom Sound Scattering Strength Measurement Method and Reverberation[D].Harbin:Harbin Engineering University,2011,40-43.
[6]张仁和,李文华,裘辛方,金国亮.浅海中的混响衰减[J].声学学报,1995;20(6):417-424.Zhang R H,Li W H,Qiu X F,Jin G L.Reverberation Loss in Shallow Water[J].ACTAACUSTICA,1995;20(6):417-424.
[7]尚尔昌,张仁和.浅海远程混响理论[J].物理学报,1975;24(4):260-267.Shang E C,Zhang R H.Long Range Reverberation Theory in Shallow Water[J].ACTAPHYSICA SINICA,1975;24(4):260-267.
[8]金国亮.均匀浅海远程平均混响强度[J].声学学报,1980;4:279-285.Jin G L.Average Intensity of Long Range Shallow-Water Reverberation Under Isovelocity Conditions[J].ACTA ACUSTICA,1980;4:279-285.
[9]金国亮,李玉昕等.南海深海混响的测量[J].声学技术,1989;1:8-11.Jin G L,Li Y X,et al.A Measure of the Deep Ocean Reverberation in the South China Sea[J].Technical Acoustics,1989;1:8-11.
[10]Love R H et al.Changes in volume reverberation from deep to shallow water in the eastern Gulf of Mexico[J].J.Acoust.Soc.Am.,2003,114(5):2698-708.
[11]R.A.Vadov.Time structure of bistaticreverberation in the long-range propagation of explosion-generated signals[J].Acoustical Physics,2007,52(2):172-180.
[12]刘伯胜,雷家煜.水声学原理(第二版)[M].哈尔滨:哈尔滨工程大学出版,2010.85-86.Liu B S,Lei J Y.Principles of underwater acoustics(Second Edition)[M].Harbin:Harbin Engineering University Press,2010,85-86.
[13]Huang Y W,Ren Q Y,Li T.A geometric Model for the Spatial Correlation ofan Acoustic Vector Field in Surface-generated Noise[J].J.Marine Sci.Appl.,2012,11(1):119-125.
[14]Harrison C H.Noise directionality for surface sources in range-dependent environments[J].J.Acoust.Soc.Am.,1997,102(5P1):2655-2662.
[15]高博,杨士莪,朴胜春.基于信道传播理论的多基地远程海底混响的研究[J].物理学报,2012;61(5):1-6.Gao B,Yang S E,Piao S C.Propagation Theory for Bi-static Long-Range Bottom Reverberation in Shallow Water Waveguide[J].Acta Phys.Sin.,2012,61(5):1-6.