Reactions of initiation of the autoignition of H-2-O-2 mixtures in shock waves

摘要

The initiation of the autoignition of hydrogen-oxygen-argon mixtures behind reflected shock waves is studied by absorption and emission spectrophotometry in the temperature range of 960 < T < 1670 K at pressures of similar to 0.1 MPa. Introduction of Mo(CO)(6) additive in an amount of similar to 80 ppm made it possible to study the effect of O atoms on the shortening of the ignition delay time of H-2-O-2-Ar mixtures. A kinetic modeling of our own and published experimental data at temperatures of 930 < T < 2500 K and pressures of 0.05 < P < 8.7 MPa enabled to establish how the initiation reactions influence the process of self-ignition and to evaluate the rate constant for one of the initiation reactions: k(H-2 + O-2 -> 2OH) = (3 +/- 1) x 10(11)exp(-E (a)/RT), cm(3) mol(-1) s(-1), where E (a) = (40 +/- 2) kcal/mol.