为了进一步提高耦合锥结构光纤超声传感器的整体性能,使其更好地服务于光纤超声无损检测,用有限元分析法仿真分析了耦合锥体材料参数对传感器响应灵敏度的影响。以此为依据挑选出4种超声聚能效果优越的锥体材料,并计算出与其匹配的最佳响应锥尖角度,优化设计了4款基于74°铝锥、30°有机玻璃锥、130°聚苯乙烯锥、126°天然橡胶锥的光纤超声传感器。实验结果表明,这4款传感器均能够有效检测频率为1 MHz的超声波信号,相比现有的传感器在响应灵敏度方面有较大提升,可以有效改善传感器的传感性能;且结构更小巧轻便,能够应用的场合更广泛。

In order to further improve the overall performance of the coupling cone structure optical fiber ultrasonic sensor and make it better serve the optical fiber ultrasonic nondestructive testing, the influence of the material parameters of the coupling cone on the response sensitivity of the sensor is simulated and analyzed by using the finite element analysis method in this paper. Based on this, 4 kinds of cone materials with excellent ultrasonic energy accumulation effect are selected and the best response cone angle is calculated to match with them. 4 optical fiber ultrasonic sensors based on 74° aluminum cone, 30° plexiglass cone, 130° polystyrene cone, and 126° natural rubber cone are optimized and designed. Experimental results show that these 4 sensors can effectively detect ultrasonic signals with a frequency of 1 MHz, and compared with the existing sensors, have a greater improvement in response sensitivity, which can effectively improve the sensor's sensing performance. Moreover, the structures are smaller and lighter, which can be used in more extensive occasions.