Experimental and modeling study of a lean premixed iso-butene/hydrogen/oxygen/argon flame

The experimental structure of a lean iso-butene/hydrogen/oxygen/argon flame (2.7% iC4H8, 4.5% H2, 83.0% O2, 9.8% Ar, ϕ = 0.225) has been determined by molecular beam mass spectrometry at low pressure (40 mbar). The detected species throughout the flame thickness were: H2, CH3, O, OH, H2O, C2H2, CO, C2H4, CH2O, O2, HO2, Ar, C3H4, C3H6, CO2, C2H4O, C4H6, iC4H8, C3H6O, C4H6O and C4H8O. An original model, validated against premixed rich C2H4, has been extended by building a sub-mechanism taking into account the formation and the consumption of species involved in iso-butene combustion. This mechanism contains 520 reactions and 99 chemical species. A good agreement appears between calculated mole fraction profiles predicted by this mechanism, compared to experimental results.