Hydroxyl radical concentration measurements in moist carbon monoxide oxidation in a chemical kinetic flow reactor

Measurements of hydroxyl radical concentration in dilute mixtures of carbon monoxide, water, and oxygen reacting in a bath of nitrogen at temperatures ranging from 989 to 1115 K and a pressure of 1 atm are reported. The measurements were made in a turbulent flow reactor using both laser absorption and laser-induced fluorescence techniques. Continuous measurements of OH concentration along the length of the reactor on the centerline were made with a movable 180 degree laser induced fluorescence probe. Line-of-sight absorption measurements, performed at three equally spaced axial locations, were used to calibrate the fluorescence data as well as to cross compare with the axially determined OH profiles. The measured OH concentrations, as well as measured stable species concentrations, are compared with predicted concentrations from a detailed chemical kinetic model. The agreement was found to be good, at worst ± 30%, yielding further validity to the proposed reaction mechanism.