分析了3层结构(封装层、弹性筒、芯轴)的芯轴干涉型光纤水听器声压灵敏度。通过建模和三维的弹性力学分析,结果表明,影响水听器探头声压灵敏度的主要因素为弹性筒的杨氏模量、壁厚、外半径以及传感光纤的长度。而封装层材料的杨氏模量、泊松比、厚度和芯轴对声压灵敏度的影响不大。制作了一批水听器样品,理论分析其声压灵敏度为-150.7 dB(re rad/μPa),实测平均值为-151.3 dB(re rad/μPa)。实测值范围为-151.9--150.5 dB(re rad/μPa),理论值与实测结果最大相差不超过1.2 dB(re rad/μpa)。实验表明,封装前、后的工艺流程对探头的声压灵敏度有一定影响。

The acoustic sensitivity of mandrel interferometric fiber-optic hydrophone with three layers(coated layer,flexible tube,mandrel) was analyzed. Modeling was built with three-dimensional elasticity analysis. Results show that the major factors which influence the acoustic sensitivity of the hydrophone are elastic modulus,wall thickness,outer radius of the tube,and sensing fiber′s length and diameter. Young′s modulus,Poisson′s ratio and thickness of encapsulation layer and mandrel have little effect on the acoustic sensitivity. A number of hydrophone samples were produced. The theoretical value of their acoustic sensitivity is -150.7 dB (re rad/μPa),and the average measured values is -151.3 dB (re rad/μPa). The range of measured values is -151.9~-150.5 dB (re rad/μPa),the difference between theoretical value and the measured value is less than 1.2 dB(re rad/μPa). Experiments also show that encapsulation process of packaging has some influence on the acoustic sensitivity.