Deflagration-to-detonation control by non-equilibrium gas discharges and its applications for pulsed detonation engine

In the present work we propose to use the non-equilibrium gas discharge plasma for preliminary gas excitation and reduction of the chemical induction time in the mixture. Synchronization of the ignition of different parts of the gas using gas discharge excitation may lead to sufficient reduction of the DDT length and improvement the efficiency of the detonation engines. The ignition dynamics under the action of nanosecond discharge (up to 100 kV voltage, up to 10 atm initial gas pressure, 300-2000 K temperature range) is discussed both for thermally equilibrium and nonequilibrium plasma. The main processes responsible for the ignition initiation and control are determined for different regimes. Measurements of ignition delay time in lean methane-air, propane-air, hexane-air and decane-air mixtures were performed in the wide pressure range from 3 to 500 atmospheres and temperatures from 750 to 1800 K using reflected shock wave technique. Ignition delay times were determined using emission at 306 nm OH(X²II ← A²Σ⁺) and absorption diagnostics at 3.3922 μm (component F₁⁽²⁾ (n ₃ = 1) ← F₂⁽²⁾(n₃ = 0) of P(7) line of n₃ mode of CH₄ molecule). The experimental data obtained were compared with the calculated by different kinetics mechanisms.