Ignition delay time correlations for distillate fuels

Ignition delay times were measured behind reflected shock waves in a shock tube for a wide variety of distillate fuels over a range of temperatures, pressures and mixtures. The fuels studied include: jet fuels (JP-5, JP-8, and Jet A), rocket propellants (RP-2), diesel fuels (F-76 and DF-2) and gasoline. A simple correlation was found to describe the ignition delay times for all these fuel/air experiments for equivalence ratios near unity, temperatures from 1000 to 1400 K, and pressures from 6 to 60 atm. A simple correlation was also found for low-fuel-concentration experiments diluted in argon. Previously published ignition delay time data were found to be in good agreement with these correlations. Finally, for several fuels studied, systematic variations were seen in the activation energy for ignition delay time measurements with varying equivalence ratio and oxygen concentration.