• Citer

Measurements of the laminar burning velocities of 1,2-butadiene: A comparative study

par Konnov, Alexander A.A.;Chen, Jundie;Lubrano Lavadera, Marco
Référence Proceedings of the Combustion Institute, 40, 1-4, page (105573)
Publication Publié, 2024-12-01

Article révisé par les pairs

• Accès en ligne
• Détails
• Contenu
• Statistiques

Résumé :

1,2-butadiene (1,2-C4H6) is one of four C4H6 isomers that could appear during pyrolysis and oxidation of heavier hydrocarbons and/or contribute to the formation of aromatic species in flames. However, it is seldom included in detailed kinetic mechanisms due to a lack of studies of its combustion characteristics. In this work, laminar burning velocities (LBV) of 1,2-butadiene flames have been measured for the first time using the heat flux method at atmospheric pressure and an initial gas mixture temperature of 298 K. To provide an unbiased experimental reference, LBV of 1,3-butadiene (1,3-C4H6) flames were also determined at the same conditions. It was found that the LBV of 1,2-C4H6 is notably higher than that of 1,3-C4H6 over the range of equivalence ratios 0.6–1.6, contrary to predictions of the recent NUIG-Mech1.3. The detailed kinetic model of the authors was extended by the reactions of C4H6 isomers with the rate constants selected from the literature and largely identical to those in NUIG-Mech1.3. Nevertheless, the present mechanism correctly reproduces qualitative trends in the LBV of C4H6 isomers. Further sensitivity and rate-of-production analyses revealed a strong coupling of the predicted pathways of 1,2-C4H6 and 1,3-C4H6 oxidation in flames. Specifically, it was found that in 1,2-C4H6+air flames reaction 1,3-C4H6+H = 1,2-C4H6+H quantitatively converts the fuel into 1,3-butadiene, leading to a similarity in the sensitivity spectra for both isomers. In addition, the LBV of 1,2-C4H6 in (O2+N2) oxidizers of different compositions were determined to provide supplementary datasets for kinetic model validation and development. Oxygen mole fraction in the oxidizer was set to 15 or 18%, while for the latter, the initial mixture temperatures were 298 or 318 K. The kinetic model correctly reproduces variation of the LBV with increased dilution by N2 or by the increase of the temperature. Despite the remaining discrepancies between experimental data and the modeling, overall good performance of the present mechanism was demonstrated for flames of 1-butyne, 2-butyne, 1,2-C4H6, and 1,3-C4H6+air flames, and 1,2-C4H6 flames with different amount of O2 in the oxidizer.