Deflagration Parameters of Stoichiometric Propane-air Mixture During the Initial Stage of Gaseous Explosions in Closed Vessels

摘要

The flame propagation during deflagration of the stoichiometric propane-air mixture ([C3H8] = 4.02 vol. %), considered as a reference test mixture., in a spherical and two cylindrical closed vessels with central ignition was monitored by means of pressure measurements, in experiments performed at ambient initial temperature and various initial pressures within 0.3 and 1.3 bar. From pressure-time records during the early stage of the process, the constants of the cubic law of pressure increase in time and the corresponding burning velocities were computed by means of an isothermal compression model. The optimal duration of the "early stage" was discussed in correlation with the flame radius at the end of this stage, computed from burned mass fractions and with the fit parameters of pressure variation versus time correlations.