| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 241384 | Proceedings of the Combustion Institute | 2011 | 7 Pages |
A method for judging the gray property of flames based on spectral analysis and the two-color method for determining the temperature and emissivity of a flame has been demonstrated. A calibrated spectrometer system was used for the data acquisition of the radiation intensity profile of a flame over a range of wavelengths (200–1100 nm). The wavelength range that meets the gray body assumption, in which the emissivity can be assumed to be constant, can be determined from the emissivity profile obtained by spectral analysis and the two-color method. Then the temperature and emissivity of the flame and their relative mean square deviations were calculated within that range. Experiments were conducted on solidified gasoline and red phosphorus flames, and pulverized coal-fired flames in a commercial 420 ton/h boiler furnace. The results show that the gasoline flame can be assumed to be a gray body in the range between 550 and 900 nm, for the coal-fired flame the range is between 500 and 1000 nm; while the red phosphorus flame cannot be assumed to be a gray body within the measurement wavelength range. The temperature and emissivity calculation results of coal-fired flames are found to be in reasonable agreement with results using other methods described in the literature. The wavelength interval in the two-color method to calculate temperature is also discussed.
