Research on Single-Source Dual-Channel Sensing System for R134a Based on NDIR Technology

In order to effectively detect and prevent the leakage of R134a in nuclear power plants, this paper studies a gas sensor based on NDIR and single-source dual-channel, which designs a dual optical path through software simulation, prepares the structural cavity using 3D printing technology, and calibrates the relationship between the concentration of R134a gas and the output voltage ratio between the signal channel and the reference channel to fit the concentration output relation. The gas chamber features an optical path length of 12.8 cm, with the light intensity absorption efficiency reaching 86%. At the same time, the equation of the relationship between the temperature and the output voltage ratio between the signal channel and the reference channel is obtained through temperature calibration, eliminating the influence of temperature on the sensor. The sensor achieves a maximum error of 57 ppm within the wide measurement range of 0-2500 ppm.