Experimental Measurements and Theoretical Analysis of Detonation Induction Distances

Abstract

Experimental measurements of the induction distances are given for hydrogen-oxygen, acetyleneoxygen, acetylene-air, methane-oxygen, carbon monoxide-oxygen, hydrogen-oxygen-nitrogen, hydrogen-oxygen-helium, hydrogen-oxygen-argon, and hydrogen-oxygen-carbon dioxide mixtures at initial pressures of 1, 5, 10 and 25 atm. An empirical relationship involving the combustion temperature, burning velocity, sonic velocity in the unburned gas and Reynolds number based on the burning velocity has been established to predict detonation induction distances of certain combustible gas mixtures. The correlation is not satisfactory for mixtures containing hydrocarbons; an explanation of this discrepancy is offered.

Combustion waves in hydraulically resisted systems

“…We emphasize that the transition here occurs without acceleration of the reaction zone, which is often considered to play a key role in the DDT. It is interesting that, for wide tubes, the predetonation time and distance are effectively independent of the tube diameter, as is occasionally observed also in conventional DDT systems [20,21]. Further experimental/numerical evidence in support of the resistance concept comes from the transition in obstructed channels open at the ignition end [22,23].…”

Numerical simulation of the deflagration to detonation transition

“…Figure 5 shows the predicted DDT run-up lengths. The experimental results of Bollinger et al [8] were used for verification. Both the numerical model and the experimental results are sensitive to the initial composition of the mixture.…”

“…A review of the literature indicates there are several relevant studies including the experimental work of Bollinger et al [8] and Hinkey et al [9], two-dimensional numerical simulations by Kailasanath et al [10], onedimensional modeling by Brüls et al [11] and Smirnov and Panfilov [12], and the comprehensive overview of the gas-phase detonation theory presented by Oppenheim et al [13]. An interesting study of the DDT behavior as a function of the activation energy and the initial gas temperature was reported by Smirnov and Panfilov [12] who studied two distinct types of DDT initiation mechanisms: initiation of detonation from the flame zone and initiation along a contact discontinuity near the primary shock wave.…”

“…An interesting study of the DDT behavior as a function of the activation energy and the initial gas temperature was reported by Smirnov and Panfilov [12] who studied two distinct types of DDT initiation mechanisms: initiation of detonation from the flame zone and initiation along a contact discontinuity near the primary shock wave. Other aspects of gas-phase detonation recently reported include the study of unsteady detonation velocities compared with theoretical CJ velocities [11,14], detonation structures [10], DDT run-up length [8,9,15], and the influence of the initial temperature and temperature gradient on the DDT process [15]. Also of interest is the critical energy required for direct initiation [14] and the abundant data available for detonation velocities of gases with elevated initial pressures provided by Bauer et al [16].…”

The effect of initial temperature on flame acceleration and deflagration-to-detonation transition phenomenon

“…The run-up distance was found to be a minimum for stoichiometric mixtures. The effect of initial mixture temperature on the run-up distance was first studied by Lafitte (1928) and later by Bollinger et al (1961). In both these studies, it was shown that the run-2.…”