J. Phys. IV France 12 (2002) Pr7-273
DOI: 10.1051/jp4:20020294

Deflagrations of non-uniform mixtures: A first experimental approach

I. Sochet¹, F. Guelon¹ and P. Gillard<sup>2

1</sup>  Laboratoire Énergétique Explosions Structures, Université d'Orléans, ENSIB, 10 boulevard Lahitolle, 18020 Bourges cedex, France
²  Laboratoire Énergétique Explosions Structures, Université d'Orléans, IUT de Bourges, 63 avenue de Lattre de Tassigny, 18020 Bourges cedex, France

Abstract
This paper is placed in a context of industrial safety. For that, we examine the more probable explosion which can be produced accidentally. In this work, we investigate the propagation behaviour of blast waves from deflagration in terms of concentration of explosive mixtures diluted into air. The dilution represents the non uniformity of the gaseous cloud versus time. Experimentally, the non uniform gaseous cloud is formed by the dispersion of a stoichiometric hydrogen-oxygen mixture initially confined in a hemispherical volume. The evolution of the blast wave is given by the pressure wave which is examined as a function of the time delay of dispersion (time between rupture of the confinement and the ignition), the position of the ignition source, and the volume of the confinement. The modelling of the dispersion of the gaseous cloud allows to control the flammability limit and correlate the blast wave propagation and the non uniformity gaseous cloud.

© EDP Sciences 2002