Journal ArticleDOI
Kinetic Studies of Hydroxyl Radicals in Shock Waves. II. Induction Times in the Hydrogen-Oxygen Reaction
G. L. Schott,J. L. Kinsey +1 more
TLDR
In this paper, the formation of OH in the shock wave induced combustion of H2 and O2 has been measured by oscillographically recording the absorption of ultraviolet OH line radiation, and the main features of the reaction course are: (1) an induction period whose length, ti, varies inversely with [O2], (2) an increase in the product [O 2] ti as ti becomes short compared to the vibrational relaxation time of O2, and (3) at the end of the induction period, a sigmoid rise of [OH] to aAbstract:
The formation of OH in the shock wave induced combustion of H2 and O2 has been measured by oscillographically recording the absorption of ultraviolet OH line radiation. The main features of the reaction course are: (1) an induction period whose length, ti, varies inversely with [O2], (2) an increase in the product [O2] ti as ti becomes short compared to the vibrational relaxation time of O2, and (3) at the end of the induction period, a sigmoid rise of [OH] to a maximum, followed by a slow decrease. ti has been studied over the ranges: 1100°≤T≤2600°K, 1.3×10—5≤[O2]≤8.0×10—4 mole/1, 0.25≤[H2]/[O2]≤5., 0.004≤[O2]/[Ar]≤0.20, and 5≤ti≤500 μsec. Agreement between incident and reflected shock experiments has been demonstrated. According to the branching chain mechanism known from explosion limit studies, ti is governed by the rate of H+O2→ lim k1OH+O according to: 2 k1[O2]ti=2.303 n, where n is the number of decades by which [OH] increases between initiation and the end of the induction period. The values of [O2]ti, which is nearly proportional to 1/k1, are summarized by: log10([O2]ti) (mole 1—1 sec)= —10.647+(3966±625)/T. The value k1=1.4×109 deduced at 1650°K from this work is combined with data near 800°K to give: k1=3×1011 exp(—17.5±3. kcal/RT) (mole/1)—1 sec.—1. The relation of these results to detonation experiments is discussed.read more
Citations
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Journal ArticleDOI
An updated comprehensive kinetic model of hydrogen combustion
TL;DR: A comprehensively tested H2/O2 chemical kinetic mechanism based on the work of Mueller et al. 1 and recently published kinetic and thermodynamic information is presented in this paper, which is validated against a wide range of experimental conditions, including those found in shock tubes, flow reactors, and laminar premixed flame.
Journal ArticleDOI
A comprehensive modeling study of hydrogen oxidation
TL;DR: A detailed kinetic mechanism has been developed to simulate the combustion of H2/O2 mixtures, over a wide range of temperatures, pressures, and equivalence ratios as discussed by the authors.
Journal ArticleDOI
Comprehensive H2/O2 kinetic model for high-pressure combustion
TL;DR: In this paper, an updated H2/O2 kinetic model based on that of Li et al. (Int J Chem Kinet 36, 2004, 566-575) is presented and tested against a wide range of combustion targets.
Journal ArticleDOI
Ignition processes in hydrogenoxygen mixtures
Ulrich Maas,J. Warnatz +1 more
TL;DR: In this article, a detailed reaction mechanism and a multispecies transport model were used to simulate the explosion limits of the hydrogen-oxygen system and the minimum ignition energies for various mixture compositions, pressures, radii of the external energy source and ignition times.
Journal ArticleDOI
Remaining uncertainties in the kinetic mechanism of hydrogen combustion
TL;DR: In this article, an analysis of the performance of an updated hydrogen combustion mechanism is presented, with particular attention paid to different channels of reaction between H atoms and HO2 radicals, to pressure dependence of the recombination of HO 2 radicals, and to the anomalous rate constant.
References
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Journal ArticleDOI
Vibrational relaxation in oxygen and nitrogen
TL;DR: In this article, a converging channel of area ratio 34 : 1 has been developed to produce strong shock waves in a tube, and values of the relaxation time τ for the approach to vibrational equilibrium behind the shocks have been measured.
Journal ArticleDOI
Photometric investigations of alkali metals in hydrogen flame gases - II. The study of excess concentrations of hydrogen atoms in burnt gas mixtures
TL;DR: In this article, the concentration of HCl, the most important chlorine compound in the hydrogen-oxygen flame gases, may be obtained from the total chlorine added to the flame gases.
Journal ArticleDOI
Calculation of Reaction Profiles behind Steady-State Shock Waves. I. Application to Detonation Waves
TL;DR: In this article, a numerical procedure for the integration of an arbitrary system of kinetic equations subject to the constraints imposed by steady state shock hydrodynamics is described, and the detonation profile has been calculated for a 2H2+O2+Xe mixture at an initial pressure of 30 mm Hg.
Journal ArticleDOI
Gaseous Detonations. IX. A Study of the Reaction Zone by Gas Density Measurements
G. B. Kistiakowsky,P. H. Kydd +1 more
TL;DR: In this paper, an x-ray absorption photometer capable of measuring gas densities with extreme rapidity and reasonable accuracy has been developed to study the reaction zone in detonation waves.