Pyrolysis study of conventional and alternative fuels behind reflected shock waves

• Fuel decomposition for two conventional fuels and six alternative fuels were measured.
• Ethylene time-histories were measured for those eight fuels.
• Current study can help refine surrogate compounds and detailed kinetic mechanisms.

Fuel decay time-histories and ethylene time-histories were measured behind reflected shock waves for JP-8 and three synthetic aviation fuels (SPK, HRJ-Camelina, and HRJ-Tallow) in 0.2–0.3% fuel/argon mixtures near 7 atm and in the temperature range 1146–1500 K, and F-76 and three synthetic navy fuels (F-76 Blend, DIM, and 103–2) in 0.15–0.3% fuel/argon mixtures near 18 atm and in the temperature range 1234–1376 K. The absorption measurements of fuel decomposition were carried out using a 3.39 μm He–Ne laser, and the overall fuel decomposition rates were inferred from the fuel decay traces. The ethylene measurements were made near 10.5 μm using a CO2 gas laser, and the peak ethylene yields were inferred for different fuels from the ethylene time-histories. The four aviation fuels show noticeably different overall fuel decomposition rates, while the four navy fuels have overall fuel decomposition rates that are close to each other. The peak ethylene yields for the four aviation fuels match each other well, while the peak ethylene yields for the navy fuels show significant fuel dependences. The current study presents the first species time-history measurements for the synthetic aviation and navy fuels covered, and provides important kinetic targets for surrogate validation and mechanism development.