北极双声道波导声传播特性分析

An analysis of acoustic propagation characteristics of dual-duct waveguide in the Arctic

北极波弗特海域下特殊的双声道声速结构对水下声传播产生深刻影响,本文利用第9次北极科学考察数据,研究了双声道波导的声传播特性,分析了波弗特声道显著声捕获能力的机理。研究发现:当声源频率足够高时,一些模态会被捕获在波弗特声道中,这些被捕获模态将不受海冰或海床影响,能量损失较小。当声源位于声道内时,激发出的被捕获模态使得声波能够远距离传播。另外,这些被捕获模态的声学特性仅与波弗特声道内的声速变化有关,在声场中传播较为稳定,能够形成稳定的干涉结构。

The special dual-duct sound speed structure significantly affects underwater sound propagation in the Beaufort Sea of the Arctic.Utilizing data from the 9th Arctic Scientific Expedition,this paper studies the sound propagation characteristics of the dual-duct waveguide,focusing on analyzing the mechanism of the remarkable sound capture capability of the Beaufort duct.The findings reveal that at sufficiently high source frequencies,certain modes will be captured in the Beaufort duct.These trapped modes will not be affected by sea ice or the seafloor,resulting in minimal energy loss.When the sound source is located within the duct,the excited captured modes facilitate long-distance sound propagation.Additionally,the acoustic characteristics of these captured modes depend solely on variations in sound speed in the Beaufort duct,ensuring their stable propagation in the sound field and the formation of stable interference structures.