Microwave and Direct-Current Discharges in High-Speed Flow: Fundamentals and Application to Ignition

Joule heating flow control methods for high-speed flows

“…Above this pressure the discharge is streamer in nature. Shibkov et al 126 agree, qualitatively, with the relation given in Eq (26). At low pressures they found that the discharge took the form of a chain of closely spaced plasma filaments i.e.…”

Numerical simulation of ethylene combustion in supersonic air flow

“…В основном технологии плазменного поджига базируются на применении электрическо-го разряда высокой мощности для нагрева и ионизации смеси [Adamovich et al, 2009;Li et al, 2013]. Также определенных успехов удалось достичь при использовании микроволнового раз-ряда для воспламенения газообразного и жидкого топлива в скоростном потоке [Shibkov et al, 2009].…”

Stabilization of liquid hydrocarbon fuel combustion by using a programmable microwave discharge in a subsonic airflow

“…Experiments have shown that all types of discharges under study initiate ignition of the supersonic flow of the propane-air mixture. Dif ferent discharges differently affect the hydrocarbon fuel ignition [28,31,32]. For example, under condi tions of a dc discharge operating at reduced electric fields E/n ~ 10-30 Td, the induction period of the supersonic propane-air flow is τ ≤ 0.1 s. The induc tion period under conditions of a pulse periodic elec trode discharge at E/n ~ 30-70 Td decreases to τ ~ (1-5) × 10 -4 s. At the same time, under conditions of a freely localized discharge operating at E/n ~ 70-120 Td, the induction period is τ ~ (2-5) × 10 -5 s. Under conditions of a surface microwave discharge at E/n~ 100-200 Td, the supersonic propane-air mix ture is ignited almost without delay immediately after turning on of the microwave energy generator τ~(1-20) × 10 -6 s. These experiments show the possibility of the nonthermal effect of the discharge plasma on the ignition of the high velocity flow of a gaseous fuel.…”

“…Block diagram of the upgraded experimental setup: (1) vacuum chamber, (2) magnetron,(3,4) synchronization system, (5) metal waveguide, (6) directed coupler, (7) crystalline detector, (8) pulsed voltmeter, (9) load, (10) dielectric antenna,(11) electrodes for initiating the dc discharge, (12) programmable microwave discharge, (13) high pressure air receiver, (14) electro mechanical valve, (15) supplying hose, (16) Laval nozzle, (17) rectangular aerodynamic channel, (18) pressure gauge,(19) ther mocouple,(20) injector,(21,22) amplifiers, (23) injector power supply unit, (24) double probe power supply unit, R is the mea suring resistance, (25) digital oscilloscope, (26) thermocouple signal amplifier,(27) double probe, (28) thermocouple, (29) noz zle for measuring the static pressure and stagnation pressure,(30,31) pressure gauges, (32) digital multichannel spectrograph, (33) monochromator,(34,35,36) light guides, (37) photomultiplier,(38,39) amplifiers, (40) digital video and photo cameras, (41) pulsed shadow setup,(42,43) computers, (44) vacuum pumps, and (45) valve.…”