Design and modeling of non-linear infrared transducer for measuring methane using cross-correlation method

Aiming to solve the drawbacks of traditional methane transducers such as narrow detecting range, poor stability, long response time, a novel methane transducer based on the principle of non-dispersive infrared absorption (NDIR) is designed. The operating principle of the NDIR and the components of the infrared transducer for measuring methane are introduced in this paper. In addition, the method of detecting the weak signal from Infrared detector based on cross correlation is proposed. The algorithms for calculation, calibration and compensation of the target methane concentration are also presented by applying the non-linear curve fitting to data point methodology for the Infrared methane transducer. The experimental results show that the accuracy, repeatability and stability of the concentration measured by the infrared methane transducer satisfy the requirements of coal mine safety management.

► Measurement principle of the infrared gas sensor.
► Hardware design of infrared methane transducer.
► A method for detecting the weak signal from Infrared detector using cross correlation.
► Models for calculation, calibration and compensation for concentration.
► Experiments are carried out to validate the models.