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Chemiluminescence experiments have been performed to assess the state of current CO * 2 kinetics modeling. The difficulty with modeling CO * 2 lies in its broad emission spectrum, making it a challenge to isolate it from background emission of species such as CH * and CH 2 O * . Experiments were performed in a mixture of 0.0005H 2 + 0.01N 2 O + 0.03CO + 0.9595Ar in an attempt to isolate CO * 2 emission. Temperatures ranged from 1654 K to 2221 K at two average pressures, 1.4 and 10.4 atm. The unique time histories of the various chemiluminescence species in the unconventional mixture employed at these conditions allow for easy identification of the CO * 2 concentration. Two different wavelengths to capture CO * 2 were used; one optical filter was centered at 415 nm and the other at 458 nm. The use of these two different wavelengths was done to verify that broadband CO * 2 was in fact being captured, and not emission from other species such as CH * and CH 2 O * . As a baseline for time history and peak magnitude comparison, OH * emission was captured at 307 nm simultaneously with the two CO * 2 filters. The results from the two CO * 2 filters were consistent with each other, implying that indeed the same species (i.e., CO * 2 ) was being measured at both wavelengths. A first-generation kinetics model for CO * 2 and CH 2 O * was developed, since no comprehensively validated one exists to date. CH 2 O * and CH * were ruled out as being present in the experiments at any measurable level, based on calculations and comparisons with the data. Agreement with

Autoignition delay time measurements were recorded for blends of CH4/n-C4H10 in “air” at pressures of approximately 10, 16, 20, 25, and 30 atm from fuel-lean to fuel-rich conditions at two different fuel compositions, 90% CH4/10% n-C4H10 and 70% CH4/30% n-C4H10, and temperatures from 660 to 1330 K in both a rapid compression machine and a shock-tube facility. A detailed chemical kinetic model consisting of 1328 reactions involving 230 species was validated using the ignition delay data from this study. This mechanism has already been used to simulate previously published ignition delay times over a wide range of conditions. It was found that the model quantitatively reproduces the ignition delays from both rapid compression and reflected shock waves, accurately capturing reactivity as a function of the temperature, pressure, equivalence ratio, and fuel composition.

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