On the burning velocity of moist carbon monoxide-oxygen-nitrogen mixtures

Abstract

Summaryo(1)It has been shown that the Tanford-Pease analysis of Jahn's burning velocity data on moist carbon monoxide mixtures does not nocessarily support their views regarding the mechanism of flame propagation.(2)A model of the combustion wave has been postulated which ignores the effects of diffusion and correlates the burning velocities in terms of the kinetic mechanisms at the flame front. This has been found to give a satisfactory fit with the experimental results of Jahn.(3)A critical comparison of the two flame theories has been made on mixtures consisting of 80 per cent CO and 20 per cent O2 with varying amounts of water. Under these circumstances, free from most of the doubtful assumptions made regarding the thermal, physical and chemical properties of Jahn's mixtures, the present views have been found to correlate the experimental data in a more satisfactory manner than the Tanford-Pease theory.(4)The effect of heavy water on the burning velocity of moist carbon monoxide mixtures has been explained in terms of the difference in reactivity between the OH and OD radical. The agreement of the predicted variation in burning velocity with experiment is satisfactory.(5)It is believed that these results indicate that the diffusion of hydrogen atoms from the burned gases may not be the controlling factor in the combustion of moist carbon monoxide mixtures. It has been shown that the Tanford-Pease analysis of Jahn's burning velocity data on moist carbon monoxide mixtures does not nocessarily support their views regarding the mechanism of flame propagation. A model of the combustion wave has been postulated which ignores the effects of diffusion and correlates the burning velocities in terms of the kinetic mechanisms at the flame front. This has been found to give a satisfactory fit with the experimental results of Jahn. A critical comparison of the two flame theories has been made on mixtures consisting of 80 per cent CO and 20 per cent O2 with varying amounts of water. Under these circumstances, free from most of the doubtful assumptions made regarding the thermal, physical and chemical properties of Jahn's mixtures, the present views have been found to correlate the experimental data in a more satisfactory manner than the Tanford-Pease theory. The effect of heavy water on the burning velocity of moist carbon monoxide mixtures has been explained in terms of the difference in reactivity between the OH and OD radical. The agreement of the predicted variation in burning velocity with experiment is satisfactory. It is believed that these results indicate that the diffusion of hydrogen atoms from the burned gases may not be the controlling factor in the combustion of moist carbon monoxide mixtures.