The autoignition of iso-cetane at high to moderate temperatures and elevated pressures: Shock tube experiments and kinetic modeling

Detailed chemical kinetic reaction mechanisms for primary reference fuels for diesel cetane number and spark-ignition octane number

“…The differences in ON for these isomers do not produce different ignition delay times at high temperatures. Many other similar studies of high temperature ignition delays for other hydrocarbons, including iso-cetane [22], confirm this conclusion. At temperatures between 650K and 900K, however, iso-cetane and iso-octane ignition is significantly slower to ignite than the n-alkanes.…”

“…Another recent study of shock tube ignition of iso-cetane, at the same conditions as those shown in Fig. 3, by Oehlschlaeger et al [22] included kinetic analysis using the present mechanism, and these experimental (filled diamonds) and kinetic modeling results are included in Fig. 3, showing excellent agreement.…”

“…Subsequent kinetic modeling by Ranzi et al [21] refined the mechanisms and added a lumped approach for the low temperature kinetic regime. In another high temperature study, Oehlschlaeger et al [22] carried out high temperature shock tube ignition delay experiments and used a detailed kinetic mechanism to analyze their results, with very good agreement between experiments and kinetic modeling results. To our knowledge, the present kinetic mechanism for iso-cetane is the first model that includes both high and low temperature regimes without lumping assumptions.…”

Detailed chemical kinetic reaction mechanisms for soy and rapeseed biodiesel fuels

“…At the same time, sensitivity analyses of these rate expressions have not shown unusually great sensitivities to most of these reaction rate expressions. In addition, computed results using these estimated rate expressions have led to reliable computed predictions of combustion rates for these fuels, so we have continued to use this technique for other classes of hydrocarbon fuels [41,54,55].…”

“…In these studies, ignition of n-heptane, n-decane, and iso-octane [43,66,67] was studied, showing very clearly a region of negative temperature coefficient (NTC) of reaction, with the amount of NTC behavior depending on the molecular structure of the fuel, as well as on equivalence ratio and pressure. Subsequently, the same test conditions have been used to test reaction mechanisms for many other fuels [37,[39][40][41]55,57,58], and further 34 experiments have been carried out to compare the intermediate temperature ignition of other fuels [54]. Part of the value of such experiments and kinetic modeling is the fact that n-heptane and iso-octane are primary reference fuels (PRF) for octane ratings of automotive fuels, and it has been interesting to use these shock tube experiments and simulations to relate other fuels to the PRF references.…”