Physics and chemistry of the influence of excited molecules on combustion enhancement

The paper addresses detailed analysis of kinetic processes in the H-2-O-2, CO-O-2 and CH4-O-2-reactive systems upon the presence of singlet oxygen molecules O-2(a(1)Delta g) and O-2(b(1)Sigma(+)(g)) and the influence of the activation of oxygen molecules in electric discharge on the acceleration of ignition in the H-2-O-2 and CH4-O-2 mixtures. The possibility of the intensification of CO oxidation due to excitation of O-2 and N-2 molecule vibrations and generation of singlet oxygen molecules is also considered. It is shown that the effect of accelerating the ignition strongly depends on the reduced electric field and, as a consequence, on the composition of discharge plasma as well as on the features of chain mechanism development in oxy-fuel systems. It is revealed that the most effective approach for the intensification of CO oxidation both in the moist air and in the products of hydrocarbon combustion in air is the generation of O-2(a(1)Delta g) molecules by electric discharge. Computations showed that the presence of 1% O-2(a(1)Delta g) in the total oxygen allowed one to convert CO to CO2 even at the temperature T = 850-900 K in the time of 10(-2) s. The excitation of O-2 and N-2 molecule vibrations is less effective for such a conversion.