FBG-Based Sensitivity Structure Based on Flexure Hinge and Its Application for Pipeline Pressure Detection

With the widespread application of pipelines in engineering, more and more accidents occur because of pipeline leakage. Therefore, it is particularly important to continuously monitor the pipeline pressure. In this study, a non-intrusive and high-sensitivity structure based on FBG (Fiber Bragg grating) sensor is proposed. Firstly, the basic sensing theory of FBG and the state of a pipeline wall under inner pressure are analyzed. Then, structural sensitivity is deduced based on the flexure hinge and mechanical lever. Subsequently, finite element simulation for the whole sensitization structure is carried out, and optimal parameters are determined to obtain the maximum sensitivity. Finally, laboratory experiments are conducted to verify the function of the designed sensitivity structure. The experimental results show a good agreement with the simulation results. In the experiment, it can be found that the designed structure has a strain sensitivity of 9.59 pm/mu epsilon, which is 11.51 times the pipeline surface strain. Besides, the structure is convenient to operate and has a good applied prospect for the engineering practice.

Automated summary

A non-intrusive and high-sensitivity structure for continuously monitoring pipeline pressure based on FBG sensor is proposed in this study. The structure demonstrates good strain sensitivity and its functionality is verified through laboratory experiments. It shows promising prospects for practical application.