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Title: Mixing and Reaction Enhancement Characteristics of Laser-Induced Plasmas and Detonations in Laser-Augmented Scramjets

Abstract

CFD simulations using a time-dependant Navier-Stokes equation with finite-rate chemistry on effects of a focused laser pulse for combustion and mixing enhancement characteristics were conducted for supersonic premixed hydrogen-air streams. From the results, it was confirmed that, depending on the laser energy density, radicals, a shock wave, and shock-induced local turbulences were being formed through the laser irradiation. Then recirculation zones with flamelets were induced. Moreover it was shown that these flamelets in the recirculation zones were being stabilized in the supersonic stream for a while. Consequently, it was shown that laser-induced plasmas could be effective in both combustion reaction and mixing enhancements for the supersonic combustion.

Authors:
;  [1];  [2]
  1. Dept. Aeronautics and Astronautics, Tokai University, 1117 Kitakaname, Hiratsuka, Kanagawa, JAPAN 259-1292 (Japan)
  2. University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8856 (Japan)
Publication Date:
OSTI Identifier:
20800233
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 830; Journal Issue: 1; Conference: 4. international symposium on beamed energy propulsion, Nara (Japan), 15-18 Nov 2005; Other Information: DOI: 10.1063/1.2203257; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AIR; COMBUSTION; COMPUTERIZED SIMULATION; ENERGY DENSITY; HYDROGEN; LASER RADIATION; LASERS; NAVIER-STOKES EQUATIONS; PLASMA; PROPULSION; PULSES; SHOCK WAVES; SUPERSONIC FLOW; TURBULENCE; ZONES

Citation Formats

Negishi, Junya, Horisawa, Hideyuki, and Kimura, Itsuro. Mixing and Reaction Enhancement Characteristics of Laser-Induced Plasmas and Detonations in Laser-Augmented Scramjets. United States: N. p., 2006. Web. doi:10.1063/1.2203257.
Negishi, Junya, Horisawa, Hideyuki, & Kimura, Itsuro. Mixing and Reaction Enhancement Characteristics of Laser-Induced Plasmas and Detonations in Laser-Augmented Scramjets. United States. doi:10.1063/1.2203257.
Negishi, Junya, Horisawa, Hideyuki, and Kimura, Itsuro. Tue . "Mixing and Reaction Enhancement Characteristics of Laser-Induced Plasmas and Detonations in Laser-Augmented Scramjets". United States. doi:10.1063/1.2203257.
@article{osti_20800233,
title = {Mixing and Reaction Enhancement Characteristics of Laser-Induced Plasmas and Detonations in Laser-Augmented Scramjets},
author = {Negishi, Junya and Horisawa, Hideyuki and Kimura, Itsuro},
abstractNote = {CFD simulations using a time-dependant Navier-Stokes equation with finite-rate chemistry on effects of a focused laser pulse for combustion and mixing enhancement characteristics were conducted for supersonic premixed hydrogen-air streams. From the results, it was confirmed that, depending on the laser energy density, radicals, a shock wave, and shock-induced local turbulences were being formed through the laser irradiation. Then recirculation zones with flamelets were induced. Moreover it was shown that these flamelets in the recirculation zones were being stabilized in the supersonic stream for a while. Consequently, it was shown that laser-induced plasmas could be effective in both combustion reaction and mixing enhancements for the supersonic combustion.},
doi = {10.1063/1.2203257},
journal = {AIP Conference Proceedings},
number = 1,
volume = 830,
place = {United States},
year = {Tue May 02 00:00:00 EDT 2006},
month = {Tue May 02 00:00:00 EDT 2006}
}
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