Development of NDIR CO2 Gas Sensing System Based on U-Shaped Optical Cavity

Abstract

In this paper, a proposed carbon dioxide Gas Sensing System of high precision, rapid reaction, compact size and low power consumption rate is presented based on the non-dispersive infrared (NDIR) measurement. This system used to determine CO2 gas concentration in air; it consists of the single broadband light source, U-shape tube optical path cavity as gas cell, thermopile detector, and microcontroller circuit. This study investigates the efficiency of the U-tube optical path cavity at CO2 gas concentrations ranging from (0-5000) ppm. The obtained results show that it has the better thermal response compare to the linear tube and exhibits high sensitivity by change the transmitted light intensity into analog voltage. The proposed system design can be used as an environmental monitoring sensor.