An experimental and modeling study of propene oxidation. Part 2: Ignition delay time and flame speed measurements

Abstract

Experimental data obtained in this study (Part II) complement the speciation data presented in Part I, but also offer a basis for extensive facility cross-comparisons for both experimental ignition delay time (IDT) and laminar flame speed (LFS) observables.To improve understanding of the ignition characteristics of propene, a series IDT experiments were performed in six different shock tubes and two rapid compression machines (RCMs) under conditions not previously studied. This study is the first of its kind to directly compare ignition in several different shock tubes over a wide range of conditions. For common nominal reaction conditions among these facilities, cross-comparison of shock tube IDTs suggests 20-30% reproducibility (2σ) for the IDT observable. The combination of shock tube and RCM data greatly expands the data available for validation of propene oxidation models to higher pressures (2-40 atm) and lower temperatures (750-1750 K).Propene flames were studied at pressures from 1-20 atm and unburned gas temperatures of 295-398 K for a range of equivalence ratios and dilutions in different facilities. The present propene-air LFS results at 1 atm were also compared to LFS measurements from the literature. With respect to initial reaction conditions, the present experimental LFS cross-comparison is not as comprehensive as the IDT comparison; however, it still suggests reproducibility limits for the LFS observable. For the LFS results, there was agreement between certain data sets and for certain equivalence ratios (mostly in the lean region), but the remaining discrepancies highlight the need to reduce uncertainties in laminar flame speed experiments amongst different groups and different methods. Moreover, this is the first study to investigate the burning rate characteristics of propene at elevated pressures (> 5 atm).IDT and LFS measurements are compared to predictions of the chemical kinetic mechanism presented in Part I and good agreement is observed.

A comprehensive experimental and modeling study of isobutene oxidation

“…For the development and validation of combustion models, it is thus crucial to improve our knowledge of detailed C4 combustion chemistry. Building a comprehensive kinetic model for isobutene is also an extension of our work on propene [2,3].…”

“…Most recently, Law and co-workers [15] reported laminar flame speeds and ignition temperatures for non-premixed counterflow flames at normal and elevated pressures. Their mechanism was built on previous studies by Zhang et al [16] and Cai et al [17] and included additional rate constants for the reactions of isobutene with Ḣ and Ö atoms and ȮH, HȮ 2 and ĊH 3 radicals.…”

“…Measured species profiles were reported as a function of temperature. Molecular species concentration profiles of O 2 , H 2 , CO, CO 2 , CH 2 O, CH 4 , C 2 H 2 , C 2 H 4 , C 2 H 6 , C 3 H 4 (allene and propyne), C 3 H 6 , acetone, acrolein, methacrolein, 1-C 4 H 8 , i-C 4 H 8 , 1,3-C 4 H 6 , 1-butyne, 2-methyl-1-butene, 2-methyl-2-butene, and benzene were obtained by probe sampling and gas chromatographs (GC) analysis. They also presented a chemical kinetic reaction mechanism capable of reproducing their speciation results.…”

A Study on Electrofuels in Aviation

“…One exception is Dataset 05 [66], where the deviation is greater. Further validation of the mechanisms used in this study can be found in [54][55][56][57][58].…”

“…For the reduction of the computation time, all hydrocarbon reactions greater than C 8 and greater than C 1 are removed in the C 8 -C 16 n-alkanes [55] and mechanisms AramcoMech 2.0 [56,57], respectively. The computation of the laminar flame speed for n-octane/air mixtures took around 60 CPU hours, while the computation of the other smaller fuels was much faster.…”