用于监测阀门泄漏的超高动态范围全光纤超声传感系统

A High Dynamic Range All-Fiber Ultra-Acoustic Pressure Sensing System for Detection of Valve Leakage

本文提出了一种超高动态范围的全光纤超声传感系统,针对阀门发生泄漏时伴随产生的声发射现象,利用光纤的光弹效应,将声发射现象产生的超声信号转换为光纤中传输的光信号的相位变化,由光路干涉结构将光信号的相位改变量转换为两路干涉输出信号的幅度量,通过相位解调还原算法和功率谱分析,实现对超声信号的探测和提取。经过阀门泄漏实地测试验证了全光纤超声传感系统的实用性和可行性,并在实验室条件下对系统的动态范围进行了具体的测试分析。

A novel high dynamic range all-fiber ultra-acoustic pressure sensing system for detection of ultra-acoustic waves emission caused by valve leakage is introduced in this paper. Based on photoelastic effect,the ultra-acoustic waves acting on sensing fiber can cause phase changes of the light transmitting in the sensing optic fiber. The interference structure in the sensing system converses phase changes into the intensity of two interference signals. Through demodulation and power spectrum analysis,the information of original ultra-acoustic signals can be extracted. The system’s practicability and effectiveness is proved by field testing and its dynamic range is calculated under laboratory conditions.