MATHEMATICAL-MODELING OF CONFINED EXPLOSIONS IN EMPTY CUBE AND DUCT SHAPED ENCLOSURES - EFFECTS OF SCALE AND GEOMETRY

The theory and experimental validation of a mathematical model of conf ined gas explosions in cube and duct shaped enclosures is presented. T he validation has concentrated upon enclosures which have one vent wit h a low failure-pressure cover filled with a quiescent homogeneous fue l-air mixture with an external atmosphere of air. Ignition was by spar k at either the centre of the vessel, or else at the closed end, oppos ite the vent. The experimental studies have enabled those physical pro cesses which have an important influence upon both the combustion rate and the rate of venting to be identified and incorporated into the mo del using both mathematical and empirical descriptions. In a compariso n with 20 experimental results, the model has been shown to closely fo llow the wide range in overpressures that result from the different si zes and geometries of the enclosures. Such a model provides a more rel iable means of extrapolating beyond the range of a given experimental dataset, to different geometries and scales, than empirically based gu idelines.