The initial stages of gaseous explosions.— Part III. The behaviour of an equimolecular methane-oxygen mixture when fired with sparks of varying intensities

Abstract

As part of the general investigation of the initial stages of gaseous explosions now being carried on by us at the Imperial College, London, we have had occasion to study photographically the behaviour of an equimolecular methane-oxygen mixture when ignited by sparks of varying intensities passed between electrodes fixed half-way along a horizontal glass tube (35 to 50 cms. long by 2 to 2·5 cms. diameter), both ends of which were closed in one series of experiments, but open in another. A few supplementary experiments were also made under other spark igniting conditions. The results of these experiments seem to be of sufficient importance, from the point of view of the interpretation of the initial stages of gaseous explosions, as to justify the separate publication of them at this juncture. The evidence of the experiments lies so much in the photographs themselves that little need be said about them beyond indicating the precise conditions under which they were obtained. It is left to each reader to study them for himself, because, while their main features will be obvious to all, the interpretation leaves room for discussion, which it is hoped this publication will provoke.