Laminar burning velocities of pyrrole/air flames: Experimental and comprehensive modeling study

Abstract

Adiabatic laminar burning velocities for pyrrole/air flames were experimentally determined using the heat flux method, over equivalence ratios ranging from 0.6 to 1.3, at atmospheric pressure and initial temperature of 338 K. The detailed kinetic model of the authors was extended by the reactions of pyrrole and its intermediates based on previous theoretical studies and analogies to reactions of similar species. A comparison of new experimental and computational results using the present and the CRECK detailed chemical kinetic mechanisms was conducted and discussed. A modification of the rate constant of reaction C4H5N+OHH2O+PYRLYL was suggested that dramatically improved the present model performance. The present and the CRECK models were then compared with other experimental targets available in the literature. Some discrepancies between experiments and model predictions and among models themselves were observed. Notwithstanding, the present model showed overall good performances in reproducing laminar burning velocities, speciation data in reactors, and ignition delay times in shock tubes. Sensitivity analyses were performed to delineate the importance of different reaction classes in pyrrole chemistry and to underline possible sources of the observed disagreements.