Download or read book Mid-infrared Laser Absorption Spectroscopy for Carbon Oxides in Harsh Environments written by R. Mitchell Spearrin and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Advancements in measurement science are presented regarding in situ laser-based detection of CO and CO2 in harsh combustion environments. Mid-infrared absorption sensing strategies, utilizing transitions in the 2.7 and 4.3 micron vibrational bands for CO2 and the 4.8 micron vibrational band for CO, were developed to enable sensitive measurements of temperature and carbon oxide concentrations in high-temperature gases. These new strategies (1) extend the utility of carbon oxide absorption sensing for hostile aeroengine applications and (2) offer significant improvements to previous methods for shock tube kinetics studies. The recent maturation of mid-infrared diode and quantum cascade lasers, combined with parallel progress in mid-infrared fiber optics, provides the platform from which the field-deployable sensors were designed. State-of-the art signal processing strategies, including calibration-free wavelength modulation spectroscopy, were implemented to tackle the thermo-mechanically harsh environments of a pulse detonation combustor and directconnect scramjet. Time-resolved and spatially-resolved measurements of temperature and carbon oxide species concentrations were demonstrated to provide an in situ metric to evaluate combustion completion for engine development. For shock tube kinetics studies, a multi-band CO2 sensing strategy was developed to provide ppm-level species detection and highly-sensitive measurements of gas temperature with microsecond temporal resolution.