Abstract

Measurement of infrared emission from hot-gas sources can be a useful method of determining temperatures and molecular species concentrations. Widening applications stem from two developments: the recent availability of commercial Fourier-transform infrared (FTIR) spectrometers that are relatively lightweight, rugged, and easy to operate, and the existence of computer programs that can readily predict changes in emission spectra with changes in source parameters. This new generation of FTIR spectrometers makes possible a wide variety of laboratory measurements that are nonintrusive, demand relatively little modification of the system being observed, and are easy to carry out. On the other hand, substantial analysis of the resulting spectra is required before quantitative estimates of system parameters can be made. We will give examples of what can be learned from emission spectra, focusing on three combustion systems: a large liquid-spray flame, a burning strand of solid rocket propellant, and the exhaust gas from apartment-building furnace stacks.

© 1990 Optical Society of America