UC Irvine

Experimental mass absorption coefficients of soot in a laboratory-scale spray combustor flame are reported for the 0.9-2.0 μm spectral range and compared to values in the literature. A specially selected JP-5 hydrocarbon fuel was sprayed through a nominal 60-deg twin-fluid nozzle at three air-to-fuel mass ratios to obtain three different soot concentrations. The measurements depended on quantitative gravimetric determination of soot concentration, gas sampling, quantitative radiometry, and optical pyrometry. Determinations of soot and gaseous species concentrations were made by traversing a water-cooled probe radially along the line of sight of the radiometer used. Optically filtered total radiometric measurements were made with selected pairs of band-pass filters. The filter bands were chosen to indicate effective gas temperature, effective soot temperature, and optical depth of soot along the radiometric line of sight. An optical pyrometer aided in confirming the soot temperature and optical depth. © American Institute of Aeronautics and Astronautics, Inc., 1990, All rights reserved.