Experimental and Numerical Investigation of Fe(CO)5 Addition to a Laminar Premixed Hydrogen/Oxygen/Argon Flame

Abstract

Abstract Low-pressure, lean, laminar, premixed hydrogen/oxygen/argon flames seeded with iron pentacarbonyl (35−170 ppm Fe(CO)5) were modeled with detailed chemistry and the results were compared to laser-induced fluorescence imaging measurements of iron atom concentration and gas-phase temperature. The model includes recent rate coefficients for the decomposition of iron pentacarbonyl and thermodynamic data. The simulated iron concentrations correspond well with the measurements with only minor discrepancies in the rise of the iron profiles at low Fe(CO)5 concentrations. In addition, it was shown that the mechanism is able to predict the effect of Fe(CO)5 on the flame speed also for lean conditions, where the model was not established yet. The major iron species, aside from atomic iron, in this flame are predicted to be FeOH and Fe(OH)2 with some FeO2 early in the flame. The observed increased flame temperatures in the presence of Fe(CO)5 are attributed to catalytic hydrogen recombination.