Publications

The impact of the third O2addition reaction network on ignition delay times of neo-pentane

Hansen, Nils H.; Kukkadapu, G.; Chen, B.; Dong, S.; Curran, H.J.; Taatjes, Craig A.; Eskola, A.J.; Osborn, D.L.; Sheps, Leonid S.; Pitz, W.J.; Moshammer, K.; Jasper, A.W.; Chen, W.; Yang, J.; Wang, Z.

The oxidation of neo-pentane was studied by combining experiments, theoretical calculations, and mechanistic developments to elucidate the impact of the 3rd O2 addition reaction network on ignition delay time predictions. The experiments were based on photoionization mass spectrometry in jet-stirred and time-resolved flow reactors allowing for sensitive detection of the keto-hydroperoxide (KHP) and keto-dihydroperoxide (KDHP) intermediates. With neo-pentane exhibiting a unique symmetric molecular structure, which consequently results only in single KHP and KDHP isomers, theoretical calculations of ionization and fragment appearance energies and of absolute photoionization cross sections enabled the unambiguous identification and quantification of the KHP intermediate. Its temperature and time-resolved profiles together with calculated and experimentally observed KHP-to-KDHP signal ratios were compared to simulation results based on a newly developed mechanism that describes the 3rd O2 addition reaction network. A satisfactory agreement was observed between the experimental data points and the simulation results, adding confidence to the model’s overall performance.