摘要
楔形海域中声传播通常会出现明显的三维效应,对声源距离估计产生显著影响。使用射线模型,首先对楔形波导中的传播损失进行计算,分析三维效应对于声波传播的影响。结果表明,随着距离的增加,水平折射效应愈加明显,所得的三维结果与使用二维模型计算所得相差逐渐增大。然后对比二维声场和三维声场中的接收波形,并对其进行模态分离,证明在某些接收位置将会出现明显的多阶模态到达或模态影区。最后通过匹配全波解以及不同号简正波所对应的脉冲波形进行声源距离估计研究,并分析三维效应对于声源距离估计结果的影响。结果表明:由于三维效应的存在,使用三维模型能够准确估计声源距离,而利用二维模型进行估计得到的结果与实际距离相差较多,总体上偏大。
Three-dimensional(3D) effects of sound propagation usually exist in wedge-shaped waveguides,which significantly affect the range estimation of sound source. Using the ray model, the transmission loss in a wedge waveguide is firstly calculated to analyze sound propagation affected by the 3D effect. The results show that the horizontal refraction effect becomes more obvious with the increase of the receiver range, and the difference between the 3D result and that calculated by using the two-dimensional(2D) model increases gradually. Then, by comparing the received pulse waveforms in 2D and 3D acoustic fields, multiple mode arrivals or modal shadow zones in some receiving positions is subsequently confirmed. Finally, source range estimation is studied by matching the pulse waveforms of full wave solution as well as the separated normal modes, and the results of source range estimation affected by 3D effect are analyzed. Due to the existence of the 3D effect, source ranges can be accurately estimated by applying the 3D model, whereas the source range estimated by 2D model greatly differs from the actual value, which is larger at most range.
引文
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