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Show measurements can be obtained for a given coal-seeded flame because the temperature is independent of the level of background in the individual spectra. No particle breakdown was observed in the spectra obtained for this study, but given higher coal feed rates and different laser energies such breakdown might be observed. Single shot measurements can be made in coal-seeded flames. These spectra can be fit successfully for temperature if the background level is less than about 20% of the nitrogen peak. Error in fitting without background subtraction demonstrated a linear relationship to background level. With proper calibration, temperatures in coal-seeded flames can be determined by fitting without background subtraction. REFERENCES Alden, M. and S. Wallin (1985) . CARS Experiments in a Full-scale (10 x 10 m) Industrial Coal Furnace. Applied Optics 24 :3434. Beiting, E.J. (1985). Coherent Interference in Multiplex CARS measurements : Nonresonant Susceptibility Enhancement Due to Laser Breakdown. Applied Optics 24: 3010. Beiting, E.J. (1986) . Multiplex CARS Temperature Measurements in a Coal-Fired MHO Environment. Applied Optics 25 : 1684. Beiting, E.J., Luthe, J. and F. Yueh (1986). Algorithms for Calculating Coherent Anti-Stokes Raman Spectra: Application to Several Small Molecules, Computer Physics Communications 42: 73. Eckbreth, A.C. (1980). CARS Thermometry in Practical Combustors. Combustion and Flame 39: 133. Eckbreth, A.C., Dobbs, G.M., Stufflebeam, J.H. and P.A. Tellex (1984). CARS Temperature and Species Measurements in Augmented Jet Engine Exhausts. Applied Optics 23: 1328. Eckbreth, A.C. (1988). Laser DiagnostiCS for Combustion Temperature and Species. Abacus Press, Cambridge, MA. Goss, L.P., Trump, D.O., MacDonald, B.G. and G.L. Switzer (1983). 10-Hz. Coherent Anti-Stokes Raman Spectroscopy Apparatus for Turbulent Combustion Studies. Rev of Scientific Instr 54: 563. Greenhalgh, D.A. (1983). RECLAS: Resonant-Enhanced CARS from C2 Produced by Laser Ablation of Soot Particles. Applied OptiCS 22 : 1128. Lucht, R.P. (1988). Coherent Anti-Stokes Raman Scattering Measurements in Coal-Particle-Laden Flames. Paper No. 88-61 at the 1988 Spring Meeting of the Western States Section, The Combustion Institute. Marko, K.A. and L. Rimai (1979). Space- and Time-Resolved Coherent Anti-Stokes Raman Spectroscopy for Combustion Diagnostics. Optics Letters 4: 211. Palmer, R.E., (1987). Personal Communication. Diagnostics Research Division 8354, Sandia National Laboratories, Livermore, CA 94550 Yueh, F.Y. and E.J. Beiting (1986). Analytical Expressions for Coherent Anti-Stokes Raman Spectral (CARS) Profiles. Computer PhYSics Communications 42: 65. 17 |