TY - GEN A1 - León, Larisa A1 - Ruwe, Lena A1 - Moshammer, Kai A1 - Seidel, Lars A1 - Shrestha, Krishna Prasad A1 - Wang, Xiaoxiao A1 - Mauß, Fabian A1 - Kohse-Höinghaus, Katharina A1 - Hansen, Nils T1 - Chemical insights into the larger sooting tendency of 2-methyl-2-butene compared to n-pentane T2 - Combustion and Flame N2 - A comprehensive, chemically detailed mechanism for the combustion of 2-methyl-2-butene and n-pentane is presented to provide insights into the different sooting tendencies of these two structurally different C5 hydrocarbons. A hierarchically assembled mechanism has been developed to specifically target speciation data from low-pressure premixed flames of 2-methyl-2-butene [Ruwe et al., Combust. Flame, 175, 34-46, 2017] and newly measured mole fraction data for a fuel-rich (ɸ=1.8) n-pentane flame, in which species profiles up to phenol were quantified. The partially isomer-resolved chemical composition of this flame was determined using flame-sampling molecular-beam mass spectrometry with single-photon ionization by tunable, synchrotron-generated vacuum-ultraviolet radiation. The presented model, which includes a newly determined, consistent set of the thermochemistry data for the C5 species, presents overall satisfactory capabilities to predict the mole fraction profiles of common combustion intermediates. The analysis of the model predictions revealed the fuel-structure dependencies (i.e. saturated vs. unsaturated and linear vs. branched) of the formation of small aromatic species that are considered as soot precursors. The propensity of the 2-methyl-2-butene flame to form larger concentrations of aromatic species was traced back to the readily available formation routes of several small precursor molecules and the efficient formation of “first aromatic rings” beyond benzene. KW - 2-Methyl-2-butene KW - n-Pentane KW - Laminar premixed flames KW - Molecular-beam mass spectrometry KW - Kinetic modeling KW - PAH formation Y1 - 2019 UR - https://www.sciencedirect.com/science/article/abs/pii/S0010218019302883#! U6 - https://doi.org/10.1016/j.combustflame.2019.06.029 SN - 0010-2180 VL - 208 SP - 182 EP - 197 ER -