Abstract
In this study, the blast wave and flame propagation behavior during a gas explosion of homogeneous premixed combustible gas confined in a spherical soap bubble have been measured simultaneously. The results show that the measured values of the over pressure at various equivalence ratios were larger than those calculated by the acoustical theory. These discrepancies were found to be arisen by the change of the flame propagation velocity in the experiment. The increase of the over pressure in lean mixtures of combustible gas might be induced by diffusive-thermal instability in the flame front. On the other hand, the increase of the over pressure in rich mixtures of combustible gas might be induced by the acceleration of the flame propagation, which is considered to be generated by the sudden rupture of the soap bubble and mixing with the surrounding air.
