Mechanisms of deflagration-to-detonation transition under initiation by high-voltage nanosecond discharges

Journal Article · Wed Oct 15 00:00:00 EDT 2008 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2008.05.019· OSTI ID:21116116

Rakitin, Aleksandr E; Starikovskii, Andrei Yu ^[1]

---

1. Physics of Nonequilibrium Systems Lab, Moscow Institute of Physics and Technology, 9 Institutski Lane, Dolgoprudny 141700 (Russian Federation)

An experimental study of detonation initiation in a stoichiometric propane-oxygen mixture by a high-voltage nanosecond gas discharge was performed in a detonation tube with a single-cell discharge chamber. The discharge study performed in this geometry showed that three modes of discharge development were realized under the experimental conditions: a spark mode with high-temperature channel formation, a streamer mode with nonuniform gas excitation, and a transient mode. Under spark and transient initiation, simultaneous ignition inside the discharge channel occurred, forming a shock wave and leading to a conventional deflagration-to-detonation transition (DDT) via an adiabatic explosion. The DDT length and time at 1 bar of initial pressure in the square smooth tube with a 20-mm transverse size amounted to 50 mm and 50{mu}s, respectively. The streamer mode of discharge development at an initial pressure of 1 bar resulted in nonuniform mixture excitation and a successful DDT via a gradient mechanism, which was confirmed by high-speed time resolved ICCD imaging. The gradient mechanism implied a longer DDT time of 150{mu}s, a DDT run-up distance of 50 mm, and an initiation energy of 1 J, which is two orders of magnitude less than the direct initiation energy for a planar detonation under these conditions. (author)

• OSTI ID: 21116116
• Journal Information: Combustion and Flame, Vol. 155, Issue 1-2; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ADIABATIC PROCESSES
EXPLOSIONS
PROPANE
ELECTRIC SPARKS
EXCITATION
MIXTURES
COMBUSTION KINETICS
OXYGEN
TRANSIENTS
TUBES
SHOCK WAVES
DISTANCE
IGNITION
STOICHIOMETRY
VELOCITY
PRESSURE RANGE KILO PA
Deflagration-to-detonation transition
Nanosecond discharges
Gradient mechanism