摘要
本文从理论上系统分析了分布式光纤传感的原理，并基于载体催化元件的工作特性提出了分布式光纤瓦斯传感的概念。利用瓦斯浓度与元件工作温度的对应关系，可以把瓦斯浓度分布的检测转化为温度分布的检测，初步实验证明该方案是可行的。
In this paper,the principles of distributed fibre optic sensor are analysedtheoretically, While the light wave transmits forword in an optical fibre,there is scatterlight along it,because of the inhomogeneous properties of the fibre。A fraction of the scatterlight travels backward.That consists of the two channels in an opticalfibre-transmit chan-nel and recieve channel.In the absence of the measurand field,when an optical pulse islaunched into an optical fibre which is of uniform properties,the variation with time of thebackscatter light power gives us the information of attenuation distribution of the fibre。Based on this theory,the transmission,attenuation and coupling of the optical pulse in thetwo channels are investigated,And a calculation formula of backscatter light power variationwith time is obtained.That lay a foundation for theoretical analysis of distributed fibre opticsensors。After analysing the operating procedure of supported catalytic sensor(SCS)theo-retically,we have got thelinear relationship between methane concentration andtheworkingtemperature,And the response of temperature to the methane concentration changes is timedependent.A detecting method of methane gas concentration distribution is firstly proposed,based on the characteristics of supported catalytic sensors and optical fiber。By making use ofthe relationship between methane gas concentration and working temperature of SCS.It ispossible to convert the detection of methane concentration to that of temperature,Prelimi-nary experiments have been done by using the optical time domain reflectometry(OTDR)andamonomode optical fibre at the wavelength of 1300nm,Experimental results proved that themethod is feasible for the measurement of methane gas concentration distribution。
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
1995年第4期387-392,共6页
Chinese Journal of Scientific Instrument
关键词
分布式光纤传感
瓦斯
检测
煤矿
Distributed fiber optic sensing,Methane,Detection,Coal mine
