AIR BLAST AND HEAT RADIATION FROM FUEL-RICH MIXTURE DETONATIONS

Large scale experiments were carried out to study the effect of fuel c oncentration on air blast parameters and heat radiation from gaseous d etonations. Hemispheric plastic envelope (4 meters in radius) was used with propane-air mixtures containing from 4 to 7 vol. % of fuel. The expressions for overpressures and impulses were determined in Sachs va riables. The effect of fuel concentration on blast parameters is shown to be insignificant for the same amount of oxygen in the mixture volu me. Thus the blast wave parameters can be described as for stoichiomet ric mixtures using additional scaling for the explosion energy accordi ng to oxygen content (cloud volume). The results of large scale experi ments with fuel spray clouds containing 0.16-100 tons of fuel with mea n concentration from stoichiometric (C-0) up to 3C(0) are reconsidered . These results confirm the proposed scaling of air blast parameters f or a wide range of fuel types, cloud volumes and fuel concentrations. Detonations of fuel rich gaseous mixtures result in a strong heat radi ation. Heat radiation energy, time and size of the fireball formed are studied as a function of fuel concentration.