| Summary: | Fossil fuel combustion is still a significant source of world energy consumption, and with the continuous development of society, human demand for energy is growing. The internal combustion engine is widely used for transportation, and its energy source is fuel combustion. The internal combustion engine has the advantage of high thermal efficiency, low cost, and a wide range of power. Improving combustion efficiency and reducing the emission of the internal combustion engine is considered a fundamental goal by combustion-related researchers all over the world. Three-component (n-heptane, iso-octane, and toluene) blended Toluene Reference Fuels (TRF) are widely used for modeling gasoline combustion. Since the detailed fuel surrogate mechanism is complicated, we study the chemical kinetic behavior of the blend of toluene and n-heptane to reduce the difficulty. This thesis discusses the construction of the kinetic reaction mechanisms of toluene, n-heptane, 1,3-cycloheptadiene (CHPD), and their blends. The study regarding CHPD is to compare the resonance stabilization of the allylic and benzylic structures. Macroscopically, the proposed models are then validated using ignition delay times across a wide range of experimental conditions from the literature and are compared with existing models. The validation and comparison results show that our proposed model is reasonably accurate. Then this thesis conducts the reaction pathway analysis and elaborates on the oxidation pathway of CHPD, n-heptane, and toluene. What is more, the sensitivity analysis combines the rate of production analysis to show the most sensitive and vital reactions in target fuel oxidation. Regarding the blended fuels, this study finds that CHPD boosts n-heptane oxidation while toluene inhibits the oxidation. CHPD is more active than n-heptane in competing for oxygen, while toluene acts like an inert when the temperature is lower than 850 K. At higher temperatures, more toluene oxidation pathways are available, and the benzene ring will open more easily, so toluene will not inhibit the overall reactivity. With higher initial pressures and higher equivalence ratios, negative temperature coefficient regions are more profound for all species and their blends. The ignition delay trend of a blended fuel will be close to the fuel which constitutes a significant portion of the mixture--Author's abstract
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