Mechanism Validation
Propane-Oxygen and Propane-Methane-Oxygen Ignition Delays
Several studies of propane-oxygen-argon and propane-methane-oxygen-argon ignition delay times behind reflected shock waves were modeled. Comparisons between computed and experimental ignition delay times are shown at the following links.
Comparisons of computed and measured ignition delays are made for the data of Borisov et al., who reported
ignition delay times of
C3H8 - O2 mixtures in Ar
using reflected shock waves with post-shock temperatures in the range from 1250 to 1700 K and pressures in the range from 0.6 to 8 atm. Ignition delay times were determined using pressure and luminosity records. To compare ignition delays measured in the same mixtures at different pressures, the
P - 0.7
pressure dependence of ignition delay
derived by Borisov et al. was used. The data
were reduced to a common postshock pressure P5 = 4 atm.
[Borisov, A.A., Zamansky, V.M., Lissianski, V.V., Skachkov, G.I., and Troshin, K.Y., Progress in Astronautics and Aeronatics, 114, 124 (1988).]
A shock-tube study of ignition delay times in C3H8 - O2 in Ar mixtures was reported by Burcat and Lifshitz in 1970. Ignition delays were determined from pressure and heat-flux measurements in the reflected shock region. The temperature range covered was from 1250 to 1600 K, the post-shock pressures ranged from 2 to 10 atm. Comparisons of computed ignition delays with their experimental data are shown in the links:
[Burcat, A., Lifshitz, A., Scheller, K., and Skinner, G.B., 13rd
Symposium (International) on Combustion, p. 745 (1971).]
Ignition delays measured in a 9.5% CH4 + 1.9% C3H8 + 19.0% O2 + 69.6% Ar mixture are compared with
computed values. The experiments were done using reflected shock waves at densities near 20 mol/m3 over a temperature range from 1300 to 1600 K . Reaction progress was monitored by calibrated pressure transducers. Ignition was defined as the point of maximum curvature in the pressure trace.
[Frenklach, M. and Bornside, D.E., Combust. Flame 56, 1 (1984).]
Mixtures of C3H8 and O2 in Ar were studied using reflected shock waves and UV laser absorption spectroscopy. Ignition delay times were derived from OH absorption profiles.
The ranges of experimental conditions were: f = 0.75 ~ 1.0, P = 3 ~ 4 atm, T = 1300 ~ 1900 K. Comparisons of computed ignition delay times with experimental data:
[Qin, Z., Ph.D. Dissertation, The University of Texas at Austin (1998).]
Ignition delay times from Spadaccini and Colket for mixtures of methane with propane are compared to computed results. Pressure transducers were used to define ignition. Temperatures ranged from 1300 to 1700 K; post-shock pressures were near 7 atm. The test gases studied contained 3.4% CH4 + 0.1% C3H8 + 7.0% O2 + 89.5% Ar and 3.29% CH4 + 0.21% C3H8 + 7.0% O2 + 89.5% Ar.
[Spadaccini, L.J. and Colket, M.B., III, Prog. Energy Combust. Sci.,
20, 431 (1994).]
