| Description of target | Sensitivity diagram | Prediction of GRI-Mech 3.0 |

DESCRIPTION OF THE TARGET

Target IG.T2: Shock tube ignition delay

Mixture: CH4-C3H8-O2-Ar (3.4%-0.1%-7%-89.5%), phi = 1.043, P = 7.095 atm, T = 1640 K

The target was selected to represent average experimental conditions for runs reported at temperatures near 1640 K, which were actually done at a wide range of pressures. The measured ignition delays, normalized to the average pressure of their 6 data points (7.095 atm) using the P^-0.56 dependence reported by the authors are shown in red in the figure to the right. The target ignition delay at this pressure is the value given by the red regression line for 10000/T = 6.1. For comparison, the 9 correspondingly normalized (to 6.24 atm, using P^-0.72) pure methane ignition delays reported by the same authors are shown in green. Reference: Spadaccini, L.J., and Colket, M.B., 'Ignition Delays in CH4-O2 and CH4-C2H6-O2 Mixtures,' (1994) Prog. Energy Combust. Sci. 20, 431.

TARGET VALUES
Experimental
(microsec)		 GRI-Mech 2.11 Trial Mech GRI-Mech 3.0
63.2 N/A 67 68.5

SENSITIVITY DIAGRAMS

The sensitivity spectra shown below were computed with a trial reaction mechanism composed of a set of 322 elementary reactions of 53 species.

Sensitivity coefficients with respect to rate coefficients Sensitivity coefficients with respect to heats of formation

Other targets