Raman scattering measurements in a side-wall quench layer

• Published in: Symposium, International, on Combustion Vol. 18; no. 1; pp. 1583 - 1590
• Main Authors: Clendening, Charles W., Shackleford, William, Hilyard, Rodger
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 1981
• ISSN: 0082-0784
• DOI: 10.1016/S0082-0784(81)80161-0

Raman-scattering measurements have been performed to investigate the effect of flame/wall interactions on unburned hydrocarbon emissions. An impervious cold (isothermal) flat wall was placed perpendicular to a laminar premixed propane/air flame, stabilized on a heat-sink-type one-dimensional-flame burner. A conventional spontaneous-Raman-scattering apparatus was utilized to obtain high-spatial-resolution data in the vicinity of the wall-burner interface. Spatial scans were obtained by translating the burner assembly with micrometer screws. Nitrogen number densities were determined by measuring Q-branch Raman spectra and by applying computer-generated corrections. The resultant densities were converted to temperatures by utilizing the isobaric nature of the flame. The inferred isotherms are qualitatively in aggreement with expectations and are reported. Hydrocarbon densities were obtained by integrating the Raman spectra in the C−H stretch spectral region. This approach is approximately equivalent to counting C−H bonds. The data exhibit a progressive disappearance of hydrocarbon, both in absolute and mole fraction terms, for translations either streamwise or away from the wall (downwind of the flame). Relative hydrocarbon number density and mole fraction profiles are reported.