EXPLOSION PRESSURES OF CONFINED DEFLAGRATIONS PROPAGATING IN STOICHIOMETRIC GASEOUS MIXTURES OF LOWER ALKANES WITH AIR

An experimental study on maximum explosion pressure in closed vessel deflagration of stoichiometric gaseous mixtures, for various initial pressures within 0.3 – 1.2 bar and ambient initial temperature is reported. Explosion pressures and explosion times of stoichiometric methane-, ethane- and propane-air mixtures were measured in a spherical vessel and in two cylindrical vessels with different diameter/height ratios. The measured explosion pressures are examined in comparison with the adiabatic explosion pressures, computed by assuming chemical equilibrium within the flame front. The influence of initial pressure and heat losses during propagation on explosion pressures and explosion times are discussed for the examined systems. Both measured and calculated explosion pressures are linear functions of total initial pressure, at constant initial temperature and fuel concentration.