Shock Tube Study of Methylcyclohexane Ignition over a Wide Range of Pressure and Temperature

Ignition delay times were measured for gas-phase methylcyclohexane (MCH)/O-2/argon and MCH/air mixtures behind reflected shock waves. Initial postshock conditions covered temperatures of 795-1560 K, pressures of 1-50 atm, fuel concentrations of 0.25-2%, and equivalence ratios (phi) of 0.5-2.0. Ignition delay times were measured using side-wall pressure and CH* and OH* emission measurements. Current measurements complement past high-pressure rapid compression machine results, are in good agreement with past low-pressure shock tube data, and significantly extend the pressure range of available shock tube ignition time data. Detailed comparisons of experimental data with predictions of available MCH mechanisms are presented, and comparisons of shock tube MCH ignition delay times to those of other important jet fuel surrogates and cyclo-alkanes are discussed.