基于光谱吸收的甲烷气体光纤传感器

摘要

In-time and accurate testing of the concentration of methane is of great social and economic significance in the safety production in coal mines. Optical fiber grating can easily get the spectrum characteristics of all kinds of gases. With low insertion loss, high reflectance, low cost, and high reliability etc, the rapid development of optical fiber sensors and gas detection techniques have great advantages over traditional ones. Based on the analysis of the near infrareds of methane molecule, using differential absorption lines of methane techniques, fiber optic sensors were designed. Taking the advantages of fiber optic sensors, the methane gas were detected on-line. With the principle of optic sensors,optical fibers are designed to combine with the network. The result shows that this monitoring system is promising in measuring the gas concentration.%甲烷是一种易燃、易爆气体,实时可靠的检测甲烷浓度对煤矿安全生产有着重要的社会意义和经济意义.光纤光栅可以很容易地得到各种各样气体的谱特性,具有低的插入损耗、高的反射率、低成本,且有很高的可靠性等特点.将光纤传感与瓦斯检测结合,具有传统检测无法比拟的优势.在分析甲烷气体光谱吸收的基础上,利用差分吸收技术,根据光纤对甲烷吸收线选择的分析,设计光纤气体传感器.利用光纤传感器的优势,实现了测量瓦斯浓度的在线检测系统,又通过监测网络由软件来实现适时测量瓦斯浓度的要求,具有较高精度和很好的应用前景.