Experimental Study of the Wave Structure of Marginal Detonation in a Rectangular Tube

摘要

Wave structure of marginal detonations, propagated through nitrogen-diluted stoichiometric hydrogen-oxygen mixtures in a 1-3/4 in. by 3/4 in. rectangular tube, is studied by the soot technique and velocity probes. Both weak shocks and strong detonations are shown to propagate transversely behind the detonation front. In marginal detonations in rectangular tubes, waves propagate in both lateral directions behind the initial shock. Ordinarily, each wave is the weak reflected shock of a triple shock interaction. Occasionally, however, as the result of a complex shock interaction, a transverse detonation is developed behind the leading shock. This produces a trace in the form of a band on a tube wall that has been previously coated with carbon soot. The width of this band is governed by the induction delay behind the initial shock. By coupling its measurement with velocity data, induction times and temperatures are obtained from self-sustained detonations. (Author)