Mechanism Generation for Hydrocarbon Fuels

ion The linear alkanes, as most simple components, provide the fundamentals of fuel modeling in the case of more complicated components (alkenes, aromatics, polycyclic aromatic hydrocarbons, etc.). Meanwhile n-alkanes or blending of n-alkanes are by far the best studied class of compounds for which reliable, detailed chemical kinetic models for combustion exist and supposed to be the suitable surrogates for practical fuels, such as kerosene [8]. In the past, the detailed kinetic mechanisms for n-heptane and iso-octane [11-12] are developed, in which the mechanism generation rule is provided by Curran et al. [9-10], with rate constants optimized such that the base chemistry from Hoyermann et al. [14] can be applied. In this thesis, this detailed kinetic model with optimized kinetics of n-heptane mechanism and hoyermann base mechanism, is used to generate reaction mechanisms both for lower and higher hydrocarbons, i.e. n-hexane and n-decane. The n-hexane mechanism is validated with shock tube experiment with lean (φ = 0.5) fuel/air mixture at 12-220atm, covering 800-1400K [36,37] .The n-decane mechanism is validated with a wide variety of experimental data, which are studied by different researchers using shock tube [39-43], jet stirred reactor [34] and plug flow reactor [45], which cover the condition at 1-80atm, ranging from temperature between 550-1200K, with very lean to fuel rich (0.25 < φ < 2) mixtures. The validation of both mechanism models indicates that important pathways and rate constants are reasonably correct, consistent with previous n-heptane study [11-12]. The reaction flow analysis and sensitivity analysis are performed to give detailed pathways during oxidation. The key pathways are consistent with previous n-heptane and iso-octane studies [9-12], which prove the reasonability of the mechanism model applied on n-hexane and n-decane.