Gaseous combustion at high pressures, Part XIV. Explosions of hydrogen-air and carbonic oxide-air mixtures at initial pressures up to 1000 atmospheres

In the previous papers of this series have been described explosions of theoretical hydrogen-air, carbonic oxide-air, etc., mixtures in spherical steel enclosures at initial pressures up to 175 atmospheres; and in 1929 our collected researches on the subject were published in a separate volume entitled “Gaseous Combustion at High Pressures,” in which their theoretical implications were fully considered in the light of the experimental evidence as a whole. Without recapitulating all the many points of interest established during the work, there was one of outstanding importance which should now be recalled, namely, the discovery, attested by an overwhelming mass of cumulative evidence, which is set forth in Chapters IX to XIII (pp. 120 to 208) of our book, of N2 -activation in CO -O2 -N2 explosions at high initial pressures due to an absorption by N2 -molecules of the radiation emitted by the burning carbonic oxide. In theoretical CO-air explosions this was marked by (i) a continuously increasing “lag” in the time taken for the attainment of maximum pressure, as the density of the medium was increased from Pi - = 10 to Pi - = 175 atmospheres, and (ii) a strong exothermic effect during the subsequent “cooling period ” (without there having been any corresponding suppression of Kinetic energy during the explosion itself ), as the activated N2 molecules slowly reverted to their normal condition. Moreover in explosions of CO-O2 -N2 mixtures containing oxygen in excess of that required for the complete combustion of the carbonic oxide, the so-activated nitrogen reacted with the excess of oxygen with the production of large quantities of nitric oxide.