Shock tube and modeling study of ignition delay times of propane under O2/CO2/Ar atmosphere

Pressurized oxy-fuel combustion is considered to be a new generation of oxy-fuel combustion technology owing to its low emission and high efficiency. In this study, the ignition delay times (IDTs) for propane under O2/CO2/Ar atmospheres were measured in a shock tube at varying pressures and equivalence ratios. A chemical kinetic model (OXYMECH 2.0) for pressurized oxy-fuel combustion was developed by updating several key elementary reactions in our previous model (OXYMECH 1.0). OXYMECH 2.0 was validated based on experimentally measured IDTs for methane, ethane, and propane in O2/CO2, O2/N2, and O2/Ar atmospheres in a pressure range of 1–250 atm, as well as laminar flame speeds (LFSs) in pressure and temperature ranges of 1–4 atm and 298–543 K, respectively. The OXYMECH 1.0, Aramco 3.0, CRECK, and DTU models were also evaluated; the results indicate that OXYMECH 2.0 performs better than other models in terms of predicting the IDTs and LFSs of C1–C3 alkanes in O2/CO2 and O2/N2 atmospheres. A detailed comparison between the OXYMECH 2.0 and Aramco 3.0 models was also performed. The influences of the pressure, equivalence ratio, and CO2 concentration on the IDTs of propane were analyzed in detail.