Experimental study of ignition behaviors of pyrolysis gas of kerosene‐based endothermic hydrocarbon fuel

Abstract

Summary The pyrolysis gas consisting of 29.4% CH4, 21.3% C2H4, 30.8% C2H6, and 18.5% C3H6 in mole fraction is presented, as the surrogate of the actual gaseous pyrolysis products. At the conditions of TC = 877.7‐963 K, PC = 3.22‐4.37 MPa, φ = 0.5 and 1.0, the ignition delays of pyrolysis gas/air (diluted with 52% Ar) have been measured. With TC or PC increasing, the ignition delay time decreases. The auto‐ignition of φ = 1.0 is faster than that of φ = 0.5. Furthermore, two widely used small hydrocarbons chemical mechanisms are validated with the measured results. The USC‐II mechanism can well predict experimental results at high‐T regimes, but fails at low‐T regimes. By sensitivity analysis of temperature, the two elementary reactions C2H6 + OH = C2H5 + H2O (negative sensitivity coefficient) and C3H6 + OH = aC3H5 + H2O (positive sensitivity coefficient) have been identified, which have higher reactivity at low‐T and lower reactivity at high‐T. Considering the extreme uncertainty of rate constants of C3H6 + OH = aC3H5 + H2O, the kinetic parameters have been modified for improving the predictions. The validated results indicate that the optimized mechanism improves predictions of the auto‐ignition behavior at low temperature regimes.