Combustion Enhancement via Stabilized Piecewise Nonequilibrium Gliding Arc Plasma Discharge

• Published in: AIAA journal 2006-01, Vol.44 (1), p.142-150
• Main Authors: Ombrello, Timothy, Qin, Xiao, Ju, Yiguang, Gutsol, Alexander, Fridman, Alexander, Carter, Campbell
• Format: Article
• Language: English
• Subjects: Air flow; Applied sciences; Combustion of gaseous fuels; Combustion. Flame; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fluidized bed combustion; Fluorescence; Geometry; Plasma; Temperature effects; Theoretical studies. Data and constants. Metering
• ISSN: 0001-1452; 1533-385X
• DOI: 10.2514/1.17018

A new piecewise nonequilibrium gliding arc plasma discharge integrated with a counterflow flame burner was developed and validated to study the effect of a plasma discharge on the combustion enhancement of methane air diffusion flames. The results showed that the new system provided a well defined flame geometry for the understanding of the basic mechanism of the plasma flame interaction. It was shown that with a plasma discharge of the airstream, up to a 220% increase in the extinction strain rate was possible at low power inputs. The impacts of thermal and nonthermal mechanisms on the combustion enhancement was examined by direct comparison of measured temperature profiles via Rayleigh scattering thermometry and OH number density profiles via planar laser induced fluorescence (calibrated with absorption) with detailed numerical simulations at elevated air temperatures and radical addition. It was shown that the predicted extinction limits and temperature and OH distributions of the diffusion flames, with only an increase in air temperature, agreed well with the experimental results. These results suggested that the effect of a stabilized piecewise nonequilibrium gliding arc plasma discharge of air at low air temperatures on a diffusion flame was dominated by thermal effects.[PUBLICATION ABSTRACT]