1-, 2- and 3-Pentanol combustion in laminar hydrogen flames – A comparative experimental and modeling study

Abstract

Oxidation pathways of three different pentanol isomers 1-, 2- and 3-pentanol are investigated using the electron–ionization molecular-beam mass spectrometry (EI-MBMS) technique. New experimental speciation data was obtained from laminar, flat, low-pressure H2/O2/Ar base flames seeded with equal amounts of pre-vaporized 1-, 2- or 3-pentanol. The experimental investigation is supported by kinetic modeling. Here, one single detailed reaction mechanism for the three linear pentanol isomers has been constructed and compared against new and existing experimental data. The model itself was obtained by an open-source reaction model generation software (RMG) and tested against existing ignition delay times, flame speeds and new quantitative experimental results for mole fraction profiles of major and intermediate species.The overall discussion of individual species profiles is guided by the model-based reaction flow analysis focusing on the initial steps of the fuel destruction paths for the three pentanols down to C3-hydrocarbon species. Therefore, the reaction pathways for the initial fuel destruction steps are shown and analyzed using combined experimental and predicted results. Analysis is performed by means of secondary decay products for each of the three pentanols. The kinetic reaction model was successfully tested against available ignition delay time and laminar flame speed data. Comparisons against 23 new quantitative species profiles are presented for each of the pentanol doped flames. In general, a good predictive capability of the detailed model can be noted for all three investigated straight-chain pentanols regarding the mole fraction profiles of major and intermediate species.