Effects of Non-Equilibrium Plasmas on Low-Pressure, Premixed Flames. Part 1: CH* Chemiluminescence, Temperature, and OH
Abstract
In this paper, we investigate the effects of nanosecond, repetitively-pulsed, non-equilibriumplasma discharges on laminar, low-pressure, premixed burner-stabilized hydrogen/O2/N2 andhydrocarbon/O2/N2 flames using CH* chemiluminescence and quantitative OH laser-inducedfluorescence (LIF) diagnostics. Two different plasma sources, both of which generate uniform,low-temperature, volumetric, non-equilibrium plasma discharges, are used to study changes inchemiluminescence, temperature, and OH concentration when non-equilibrium plasmas aredirectly coupled to conventional hydrogen/hydrocarbon oxidation and combustion chemistry.Qualitative imaging of CH* chemiluminescence indicates that during plasma discharge, theluminous flame zone is shifted upstream towards the burner surface with little change in the CH*zone thickness. For the same plasma discharge and flame conditions, quantitative results usingspatially-resolved OH LIF and multi-line, OH-LIF thermometry show significant increases inground-state OH concentrations in the preheating zones of the flame. More specifically, for aparticular axial position downstream of the burner surface, the OH concentration increases,which can be viewed as an effective shift of the OH profiles towards the burner surface. Theincrease in OH concentration is conceivably due to an enhancement of the lower-temperaturekinetics including O atom, H atom and OH formation kinetics and temperature rise due to thepresence of the low-temperature, non-equilibrium plasma.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2016
- Accession Number
- AD1001121
Entities
People
- Igor V. Adamovich
- Jeffrey A Sutton
- Ting Li
Organizations
- Ohio State University