Research On Photothermal Catalytic Gas Leakage Optical Fiber Sensor

Natural gas as a clean energy is flammable and explosive medium,it must avoid being leaked during use.The traditional catalytic combustion gas leak detection sensor internal integrates the resistance heating unit,it is easy to bring security risks.How to realize the essential safety of gas leak sensor is the focus of research in this field.The research of this paper is based on the catalytic combustion effect of methane,an all-optical heating mode is used.The low temperature ignition characteristics of catalytic combustion of different kinds of catalysts were analyzed in detail,Catalyst with a low temperature ignition characteristic is preferred through the electric heating contrast.The fiber grating temperature sensor is used to detect the heat released by low temperature catalytic combustion,the photothermal conversion film and the laser source with pigtail were explored by experiment.Different light heating structures are designed and compared.The structure of the sensor chamber is designed and implemented.The light source system platform is built,the actual photo-thermal conversion system is tested and analyzed through the selection of the blackbody structure and the reflective absorption structure.In the case of equal output power of the light source,the actual temperature rise of the blackbody structure can reach 123 ?,the ignition temperature of the selected catalyst is fully met.The actual temperature rise of the reflection-absorption structure reaches 76 ?,while if the light source output power continues to increase,the ignition temperature of the selected catalyst can still be met.Through the verification experiments by catalyst and light heating,the feasibility of the light and heat catalytic gas leaked fiber optic sensor is confirmed.The sensor's core probe is all-optical without electricity,the safety monitoring of gas leaks is assured to a certain extent,it has a good application prospect in the field of gas leak monitoring.