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Title: Laser-saturated fluorescence of nitric oxide and chemiluminescence measurements in premixed ethanol flames

In this study, nitric oxide laser-saturated fluorescence (LSF) measurements were acquired from premixed ethanol flames at atmospheric pressure in a burner. NO-LSF experimental profiles for fuel-rich premixed ethanol flames ({phi} = 1.34 and {phi} = 1.66) were determined through the excitation/detection scheme of the Q{sub 2}(26.5) rotational line in the A{sup 2}{sigma}{sup +} - X{sup 2}{pi} (0,0) vibronic band and {gamma}(0,1) emission band. A calibration procedure by NO doping into the flame was applied to establish the NO concentration profiles in these flames. Chemiluminescent emission measurements in the (0, 0) vibronic emission bands of the OH{sup *} (A{sup 2}{sigma}{sup +} - X{sup 2}{pi}) and CH{sup *}(A{sup 2}{delta} - X{sup 2}{pi}) radicals were also obtained with high spatial and spectral resolution for fuel-rich premixed ethanol flames to correlate them with NO concentrations. Experimental chemiluminescence profiles and the ratios of the integrated areas under emission spectra (A{sub CH*}/A{sub CH*}(max.) and A{sub CH*}/A{sub OH*}) were determined. The relationships between chemiluminescence and NO concentrations were established along the premixed ethanol flames. There was a strong connection between CH{sup *} radical chemiluminescence and NO formation and the prompt-NO was identified as the governing mechanism for NO production. The results suggest the optimum ratio of themore » chemiluminescence of two radicals (A{sub CH*}/A{sub OH*}) for NO diagnostic purposes. (author)« less
Authors:
; ; ;  [1]
  1. Aerothermodynamic and Hypersonic Division, Institute of Advanced Studies - General Command of Aerospatial Technology, Rodovia dos Tamoios, km 5.5, 12228-001 Sao Jose dos Campos - SP (Brazil)
Publication Date:
OSTI Identifier:
21350384
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 34; Journal Issue: 8; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; NITRIC OXIDE; CHEMILUMINESCENCE; ETHANOL; FLUORESCENCE; COMBUSTION; RADICALS; EMISSION SPECTRA; EXCITATION; HYDROXYL RADICALS; ATMOSPHERIC PRESSURE; BURNERS; CALIBRATION; DETECTION; CORRELATIONS Premixed flames