LASER IGNITION OF COMBUSTIBLE GASES BY RADIATIVE HEATING OF SMALL PARTICLES

This article summarizes the ignition risks of laser power delivered by optical fiber to combustible atmospheres. Of six possible ignition mechanisms, the ignition of a combustible gas by a small optically heated body has been extensively investigated. Continuous-wave (CW) powers of 100 mW delivered by multimode optical fibers created explosion in combustible atmospheres. A numerical model of the ignition of a combustible gas by a small heated body on the exposed end of an optical fiber is developed. Important parameters include gas (type and concentration), particle (type, diameter, absorptivity, refractive index, reactivity, thermal capacity, density), optical fiber (core diameter and numerical aperture), and light (wavelength and power).