Kinetic modeling is conducted with a 2-component surrogate (10%n-dodecane/90n-dodecane/90%ecand) and a single component surrogate (2-methylnonane) to evaluate the potential to predict ignition behavior of the HRJ fuels.
Under most conditions, the 2-component surrogate provides better prediction of ignition behavior, but the single component surrogate is superior at low pressures near the negative temperature coefficient region.
A three component surrogate fuel for POSF 4658 has been formulated by constraining a mixture of n-decane, iso-octane and toluene to reproduce the hydrogen/carbon ratio and derived cetane number of the target fuel.
Multi-component surrogates, formulated by matching the octane ratings and compositions of the two gasolines, emulated the autoignition behavior of gasolines from high to low temperatures.
A major challenge, however, is the capability to design compact and reliable kinetic models that capture all the specificities of the simpler, but still multi-component surrogates.
A major limitation however, is the capability to design compact and reliable kinetic models that capture all the specificities of the simpler, but still multi-component surrogates.
Homogeneous charge compression ignition (HCCI) engine simulations were used to show that the PRF and multi-component surrogates exhibited similar combustion phasing over a wide range of engine operating conditions.
Reactivity of HSRN was compared, via experiments and simulations, with three suitably formulated surrogates: a two-component PRF (n-heptane/iso-octane) surrogate, a three-component TPRF (toluene/n-heptane/iso-octane) surrogate, and a six-component surrogate.
The chemical kinetic contribution provided by the specific fuel chemistry has thus been elucidated for tested individual component and multi-component surrogate fuels.
However, at low temperatures (T < 750 K), the six-component surrogate performed the best in emulating the reactivity of naphtha fuel.
The 6-component surrogate captures the same trend correctly, but the agreement is not quantitative with respect to some of the aromatics such as benzene and toluene.
