Induction distances, transient pressures, and wave propagation rates were determined in cylindrical tubes for detonation waves in stoichiometric hydrogen-oxygen mixtures initially at one atmosphere and temperatures ranging from 300°K down to 123°K. The induction distances became considerably shorter as the initial gas temperature was decreased. The maximum pressure ratio in the induction region (ratio of the pressure at the point of onset of detonation to the calculated Chapman-Jouguet detonation pressure) was also observed to decrease at lower temperatures although the maximum pressure attained in the induction region was very nearly the same in all cases. The decrease of the induction distance with decreasing initial gas temperature is assumed to be caused by the decrease of the speed of sound of the unburnt gas and an increase of the flame acceleration. For a better understanding of the detonation induction process the normal burning speeds of stoichiometric hydrogen-oxygen mixtures were measured at temperatures from 500°K to 123°K. The normal burning speeds were found to be proportional to the absolute temperature of the unburnt gas. © 1969.
