Closed vessel combustion of propylene–air mixtures in the presence of exhaust gas

The pressure–time evolution during the deflagration of gaseous propylene–air mixtures in the presence of their own exhaust gas was experimentally investigated in a spherical vessel, over an extended range of equivalence ratios, at room temperature and various initial pressures within 0.3–1.0 bar. The characteristic parameters of closed vessel explosions (peak pressure, maximum rate of pressure rise, time necessary to reach the peak pressure, explosion index) are examined in connection with the fuel/oxygen ratio and with exhaust gas concentration. The measured flammability parameters together with the computed values of adiabatic explosion pressures and adiabatic flame temperatures are used to examine the inerting effect of exhaust gas.