TEMPERATURE AND SOOT VOLUME FRACTION STATISTICS IN TOLUENE-FIRED POOLFIRES

The probability density functions and the temporal characteristics of local instantaneous emission and absorption properties in strongly rad iating toluene pool flames are presented. Measurements show a large dy namic range in the data resulting from the distribution of soot partic les in narrow regions within the fire and from the nonlinear dependenc e of Planck's function on temperature. The importance of the different frequencies of turbulent fluctuations of emission properties and thei r effect on monochromatic radiation intensity is investigated using a filtering technique. This technique found that the fluctuations in loc al emission intensities made the largest contribution to the fluctuati ng nature of the radiation leaving the flame. The pulsation frequency of the large-scale motion of the fire was found to be the cutoff below which the removal of turbulent fluctuations would affect the mean and RMS intensity. Resolution of frequencies above this limit leads to re asonable estimates of mean and RMS intensity.