Measurement of the rate coefficient of H+O2+M→HO2+M for M=Ar and N2 at high pressures Academic Article uri icon


  • OH mole fraction profiles were measured using cw UV laser absorption in shock-heated mixtures of H2/O2/Ar/N2 between 1260 and 1375 K at 50, 68, and 115 atm. Rate coefficients for the reaction H+O2+M→HO2+M, M=Ar and N2 were inferred by comparison of measured OH profiles with OH profiles modeled using the GRI-Mech v1.2 mechanism. The rate coefficient data were fit with pressure-dependent expressions that use k∞ and Fcent from Cobos et al. [3]. For M=Ar, the measured third-order rate coefficients are consistent with a pressure-dependent expression that uses k0=7×1017T-0.8 [cm6/mol2/s] from GRI-Mech v1.2. For M=N2, the present data, when combined with the lower-temperature value of Bromly et al. [15], are consistent with a pressure-dependent expression that uses k0=2.6×1019T-1.24 [cm6/mol2/s] over the temperature range of 700-1375 K. This expression yields k0 values that are substantially higher than the GRI-Mech v1.2 recommendation but consistent with previous flow reactor, flame, and shock tube data and the review of Baulch et al. [24]. © 1996 Combustion Institute.

author list (cited authors)

  • Davidson, D. F., Petersen, E. L., Röhrig, M., Hanson, R. K., & Bowman, C. T.

citation count

  • 19

publication date

  • January 1996