纳机电矢量水听器耐压结构设计

纳机电矢量水听器具有低频性能好,灵敏度高等性能优点,在深海探测领域具有巨大的应用潜力,为满足超深水工作的要求提出了绝缘托盘式新型封装结构,解决了纳机电矢量水听器的耐高静水压技术难题。首先,进行聚氨酯透声帽外围封装承压分析,理论论证聚氨酯基体树脂材料的极限耐静水压强度为42.3 MPa。然后,对MEMS芯片输出电压进行理论计算以及对其进行模态仿真,得出在高达20 MPa的静水压作用下,传感器的输出灵敏度基本无变化,而且工作频带有所拓宽。测试结果表明:改进封装的纳机电矢量水听器在高压20 MPa时,可以实时获得敲击信号;加压前后,该水听器在20 Hz~1 000 Hz工作频带内水听器的灵敏度和指向性基本一致。

The design of pressure-resisting structure for NEMS vector hydrophone

The NEMS (Nano-Electromechanical System) vector hydrophone, which has advantages of low frequency, high sensitivity, etc, has huge potential for application in deep ocean detection. A novel encapsulation structure of insulation tray was proposed to meet deepwater work requirements, which solved the problem of high pressure-resisting for NEMS vector hydrophone. First, pressure-resisting analysis of the polyurethane sound-transparent cap was conducted, and the theoretical demonstration shows that the ultimate pressure-resisting capacity of polyurethane substrate material is 42.3MPa. Then, this paper conducted theoretical calculation about the output voltage of the MEMS chip and completed its mode simulation. The analysis results reveals that the sensitivity of hydrophone is changed rarely, even in the high hydrostatic pressure at 20MPa , and the working frequency band is broaden. Finally, the hydrophone was tested. Results show that the NEMS hydrophone with improved structure can obtain knocking signals in high hydrostatic pressure at 20Ma; Comparing results before and after the pressure testing, there is almost no change about the sensitivity and directional pattern of NEMS vector hydrophone.