Influence of the chamber volume on the upper explosion limit for hexane–air mixtures

Fundamental hexane vapour–air explosion parameters were found by measuring the explosion pressure variation in closed chambers of 5.6 and 40 dm3 volume. Also the explosion pressure and rate of explosion pressure rise of hexane droplets–air mixtures close to upper explosion limit were obtained for chambers of 5.6, 40, 150 and 1250 dm3. It was found that the upper explosion limit for hexane droplets–air mixture is in the range of 1.8–5.5 kg/m3 and is about 30–40 times higher than the stoichiometric concentration and 3–9 times higher than that for hexane vapours–air mixtures. It was stated, that rich explosion limit is increasing along with an increase of the droplets mean diameter and also along with the chamber size. 3D and large eddy simulation of the investigated process with using computer code FLUENT 6.0 was also made.