At lower temperatures i e ndash

Measurements of ignition delay times spanning low, intermediate, and high temperatures were carried out in a heated high-pressure shock tube (HPST) at Rensselaer Polytechnic Institute (RPI) using the reflected shock technique. This shock tube has been described by Wang and Oehlschlaeger [19] and references therein, hence, only details relating to the present study PHA-767491 provided here. Ignition delay times were measured for fuel/air mixtures at equivalence ratios of 0.5 and 1.0, temperatures ranging from 714 to 1262 K, and nominal pressures of 20 and 40 bar. Reactant mixtures were prepared by direct injection of fuels into a heated mixing vessel. Following vaporization of the fuel, N2 and O2 were added in emphysema order to the mixing vessel from compressed gas cylinders at a molar ratio of 3.76:1; reactant mixture molar fractions were specified via partial pressure. The ignition event was measured by monitoring the pressure history, and the ignition delay time has the same definition as in the LPST. Following the passage of the reflected shock wave, the pressure was observed to slowly rise due to viscous gas dynamics at a rate of dP/dt = 2–3% per millisecond, which is incorporated into kinetic modeling simulations. The uncertainty in ignition delay is ±20% (95% confidence interval), where the majority of ignition delay uncertainty stems from uncertainty in the reflected shock temperature.