A Robust Method for Tuning Photoacoustic Gas Detectors

Abstract

Abstract-Detection of gases in industrial contexts is of great importance for ensuring safety in storage and transport, so as to limit atmospheric pollution and precisely control industrial and agricultural processes. Although chemical sensors are in widespread use, solidstate infrared detectors for gas sensing promise numerous advantages over conventional catalytic detectors in terms of sensitivity, calibration requirements, and lifetime. The laser-modulation photoacoustic approach is an alternative. Compared to other approaches, it provides more precise measurements with a stable zero baseline, as well as having significantly less complicated optics than cavity ringdown approaches. One enduring problem, though, is the relatively long time required to make photoacoustic measurements. The key contribution of this paper to the industrial context is twofold: first, we show how a sensitive dual-buffer acoustic resonator may be fabricated using 3D printing, and secondly we describe a method for localizing the peak absorption more rapidly than stepping a laser through the gas absorption profile. Modelling of the proposed approach demonstrates its potential, and the expected results are confirmed using an extensive experimental setup for the detection of methane in air.Index Terms-gas leak detection, infrared detectors, natural gas industry

Review Study on Recent Developments in Fire Sensing Methods

“…In some literature, the acoustic signal parameters like the speed of the sound, its attenuation, and its acoustic impedance get altered with the change in parameters of sensing material like concentration of the target gas, gas density, etc. [75][76][77][78][79][80][81]. Many fire detection technology based on the electronic nose concepts has been reported in the literature.…”

Recent Advances in Sensors for Fire Detection

“…A gas detecting method based on acoustics is reported in the literature, which displays a change in acoustic wave velocity due to the variation of particular parameters (such as mass) of sensing material [90,91]. The measuring gas is passed through by a wavelength or intensity-modulated LASER beam.…”