title: Fast combustion waves and chemi-ionization processes in a flame initiated by a powerful local plasma source in a closed reactor.
abstract: Results are presented from experimental studies of the initiation of combustion in a stoichiometric methane-oxygen mixture by a freely localized laser spark and by a high-current multispark discharge in a closed chamber. It is shown that, preceding the stage of 'explosive' inflammation of a gas mixture, there appear two luminous objects moving away from the initiator along an axis: a relatively fast and uniform wave of 'incomplete combustion' under laser spark ignition and a wave with a brightly glowing plasmoid behind under ignition from high-current slipping surface discharge. The gas mixtures in both the 'preflame' and developed-flame states are characterized by a high degree of ionization as the result of chemical ionization (plasma density n(e)≈10(12) cm(-3)) and a high frequency of electron-neutral collisions (ν(en)≈10(12) s(-1)). The role of chemical ionization in constructing an adequate theory for the ignition of a gas mixture is discussed. The feasibility of the microwave heating of both the preflame and developed-flame plasma, supplementary to a chemical energy source, is also discussed.
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: K V
authors.initials: KV
authors.lastname: Artem'ev
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: N K
authors.initials: NK
authors.lastname: Berezhetskaya
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: S Yu
authors.initials: SY
authors.lastname: Kazantsev
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: N G
authors.initials: NG
authors.lastname: Kononov
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia kossyi@fpl.gpi.ru.
authors.forename: I A
authors.initials: IA
authors.lastname: Kossyi
authors.affiliation: D. V. Skobeltsyn Institute of Nuclear Physics, Moscow State University, Leninskie Gory, 2, Moscow 119991, Russia.
authors.forename: N A
authors.initials: NA
authors.lastname: Popov
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: N M
authors.initials: NM
authors.lastname: Tarasova
authors.affiliation: Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya Street 13, Building 2, Moscow 125412, Russia.
authors.forename: E A
authors.identifier: http://orcid.org/0000-0003-4249-8655
authors.initials: EA
authors.lastname: Filimonova
authors.affiliation: A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Vavilov Street 38, Moscow 119991, Russia.
authors.forename: K N
authors.initials: KN
authors.lastname: Firsov
keywords: fast combustion wave; non-equilibrium chemi-ionized plasma; powerful discharge