Transient Measurements of Radiative Properties, Soot Volume Fraction and Soot Temperature in a Large Pool Fire∗

Turbulence radiation interaction modeling in hydrocarbon pool fire simulations

“…In contrast, the data provided by Gore, et al (1992) suggests a consistent shift to colder temperatures in the temperature pdf along the fire centerline for the heavily sooting acetylene flame. This cold shift is also reflected in the data provided by Gritzo, et al (1998). Krebs, et al also show that the temperature pdf takes on a distinctly bimodal form within the reacting shear layer where intermittence between the cool oxidizer stream and hot combustion products is more pronounced.…”

“…Gore, et al (1992) and Gritzo, et al (1998) both considered unconstrained combustion of more heavily sooting fuels in air including acetylene and aviation fuel. All of these authors show that while the pdf of the temperature fluctuation takes a generally Gaussian distribution at many locations in the fire, distinct deviations from a purely Gaussian profile may also be seen.…”

“…,.. Gritzo, et al, (1998) measured extinction coefficients within a large hydrocarbon pool fire on the order of 10 m-l. On this basis, and using the optically thin limit suggested by Krebs, et @. (1996), the thin eddy approximation would be valid for turbulent eddies of up to 3 cm for large scale hydrocarbon pool lires.…”

Temporal Evolution of Soot Particles from C2H2/O2 Combustion in a Closed Chamber

“…The soot volume fraction from laser extinction (I/I 0 = 0) was measured up to 3 ppm, as the upper limit of detection of our system. This limit value was reached in the time interval of 3.0-4.0 ms for all the flames studied and presents the same magnitude as that observed at several different flame regions in a large fuel pool fire experiment 25 and in laminar / turbulent flames. 2,9 The soot volume fraction for the combustion of all mixtures studied changes as a function of time, resulting in different velocities of soot formation, as indicated in Figure 7.…”

“…By considering that soot particles are approximately spherical, the soot volume fraction (f v ) can be evaluated by: 25 (1) where τλ is the measured transmittance, λ is the wavelength of laser light emission, kλ is the absorption coefficient per unit of volume fraction of soot (4.892 at 632.8 nm) 25 and s is the uniform sample volume path length. Figure 7 shows the soot volume fraction as a function of time calculated from the laser extinction of the combustion processes.…”