工程化光纤光栅液体压力传感器的研制

Development of FBG-based liquid pressure sensor for engineering

液体压力是流体压力管道结构的重要荷载，传统的液体压力传感装置无法满足长期监测对其稳定性与耐久性的要求。基于双光纤光栅感知原理，针对某重点工程项目的环境条件，设计开发出了一种满足工程应用需求的液体压力传感装置，给m了详细的理论分析，并通过大量的标定试验分析了该装置的传感特性，理论与实验数据吻合很好，相差小于3％。根据随机抽取的100个传感器的标定数据，采用统计分析方法得到了该类传感器的各性能指标：测量范围0～2．5MPa，分辨率〈0．4％F·S，迟滞〈2．4％F·S，重复性〈2．3％F·S，线性度〈2．1％F·S，总精度〈4％F·S，结果表明该传感器具有温度自补偿、线性度和重复性好、精度较高等优点，适合压力管道结构液体压力测试，具有良好的应用前景满足实际工程需要。

Liquid pressure is one of the most important loads in head conduit construction. It is still a big challenge to set up a durable and stable long-term liquid pressure monitoring system under harsh environment with traditional liq- uid pressure sensor. In this paper, in consideration of the environmental condition of a certain major project, based on dual fiber Bragg grating （FBG） sensing principle, a FBG-based liquid sensor structure is developed and optimized, and its sensing principle is also given in details. The novel sensor was tested in a great number of calibration experi- ments;and the experiment data are consistent with the theoretical analysis nicely, their difference is less than 3%. The calibration data of randomly selected 100 sensors were analyzed with statistical method;and the main perform- ance indexes are as follows ： the measurement range is 0-2.5 MPa, the resolution is less than 0.4% F· S, the hyster- esis is less than 2.4% F·S, the repeatability is less than 2.3% F · S, the linearity is less than 2.1% F·S, and the overall accuracy is less than 4% F · S. The research results show that the FBG-based liquid pressure sensor has good linearity, repeatability, accuracy and self temperature compensation ability;and the theoretical sensitivity agrees well with that of the experiment results. The proposed FBG-based liquid pressure sensor is suitable for the liquid pressure test in head conduit construction, can meet the actual engineering requirements and has bright application prospect.