Vibrational Nonequilibrium Effects in the (H2, H2) Reactive System

The decrease in the forward rate of the (H2, H2) reaction from its equilibrium value due to the perturbation of the vibrational distribution function by reaction is calculated from a numerical solution of a non-linear Master equation. The inelastic and reactive cross sections that are required for this calculation were obtained from a Monte Carlo average of many quasiclassical collision trajectories. At 3200°K, the highest temperature studied, the decrease in the equilibrium rate of reaction was 0.21%. The vibrational relaxation time for H2 in the absence of reaction was also calculated and found to obey a Landau-Teller temperature dependence (Pτ)calc=62× 10−9 exp (148/T1/3) atm·sec. over the range 1200–3200°K.