The effect of vent size and concentration in vented gasoline-air explosions

Experimental data from vented explosion tests using gasoline-air mixtures with concentrations from 0.88 to 2.41% vol. are presented. A 2L vessel was used for the tests with vent sizes of 25 cm2, 50 cm2 and 100 cm2. The tests were focused on the effect of gasoline vapor concentration and vent size on the pressure development and the flame behavior inside and outside the vessel. It was found that the inner flame propagation speed was mainly dependent on the initial concentration, while the maximum flame spreading distance was mainly influenced by the vent size. The external flame speed and duration could be influenced by the combination of the two properties. The internal pressure increases gradually with the flame propagated inside the vessel and decreased sharply when the vent failed. High-pressure durations containing pressure peaks were recorded by transducers in front of the vent and oscillations could be observed besides the vent. At any measure point, the maximum external pressures for A = 25 cm2 or 50 cm2 were significantly larger than those for A = 100 cm2.