【摘要】 为了提高光纤水听器在深海环境中检测声波的灵敏度，设计了一种基于推挽式结构的深海光纤水听器基元，可以实现深海3 000 m处10 Hz～2 kHz目标水声信号的有效探测。首先，基于Michelson干涉仪介绍推挽式深海光纤水听器的构成与声压灵敏度理论，接着利用弹性力学理论分析声压转换机理，通过有限元方法模拟仿真水听器探头的弹性筒结构尺寸参数对声压灵敏度的影响，并针对水听器在深水环境下工作的稳定性进行了探究。根据计算结果分别制作了5组不同结构和制作工艺的光纤水听器基元。最后，通过高静水压灵敏度系统测试，模拟5组光纤水听器在深海3 000 m处的工作性能，验证水听器弹性筒的结构参数和制作工艺对其在深海环境中声压灵敏度的影响。实验结果显示，光纤水听器基元的结构和制作工艺可以显著地影响其在深海环境中工作性能和稳定性，经过结构参数和制作工艺优化后的光纤水听器在深海3 000 m处10 Hz～2 kHz频带范围下的水声信号的响应，其平均声压灵敏度可达到-127 dB re rad/μPa，相比优化前提高了7 dB re rad/μPa。综上所述，优化后的水听器基本满足深海高静水压下声波的高灵敏可靠探测要求。更多还原

【Abstract】 In order to improve the acoustic sensitivity of a fiber optic hydrophone in a deep-sea environment, a deep-sea fiber optic hydrophone element based on a push-pull mandrel structure was designed. It could effectively detect target underwater acoustic signals of 10 Hz-2 kHz at 3 000 meters in the deep sea. First, based on the Michelson interferometer, the composition and acoustic sensitivity of the fiber optic hydrophone with a push-pull mandrel structure were introduced. Then, the acoustic pressure conversion mechanism was analyzed using elastic mechanics theory. Afterward, the influence of the elastic tube structural parameters of the hydrophone primitives on acoustic sensitivity was simulated via the finite element method. Meanwhile, the working stability under deep-sea conditions was explored. According to the calculation results, five groups of fiber optic hydrophone elements with different structures and manufacturing processes were fabricated. Finally, the working performance of the five groups of fiber optic hydrophones at 3 000 meters deep-sea was tested using a high hydrostatic pressure acoustic sensitivity system to verify the influence of structural parameters and manufacturing processes on acoustic sensitivity in a deep-sea environment. The experimental results show that the structure parameters and fabrication process of fiber optic hydrophone can significantly affect its working performance and stability in deep-sea environment. After optimization, the fiber optic hydrophone′s response of underwater acoustic signal in 10 Hz-2 kHz frequency band at 3 000 meters deep-sea can reach-127 dB re rad/μPa, which is 7 dB re rad/μPa higher than before. It basically meets the requirements of high sensitivity and reliable detection of sound waves for deep-sea application.更多还原