Mehdi ABBASI, Ali NATEGHI
DOI Number: 10.60853/pzfb-c361
Conference number: HiSST-2024-0073
Diesel fuel is widely used in transportation sections worldwide, such as in road- and railway, as well as in aviation. Despite its importance, the number of existing theoretical studies focused on its combustion characterization, particularly on kinetic surrogate modeling, remained limited. This issue became the topic of recent researches of us. The recently published diesel surrogate model by the authors consists of a semi-detailed kinetic model and three surrogate formulas, including four components, namely: n-dodecane, iso-octane, toluene and cyclohexane, with various mole fractions. As found in previous research, the high-temperature reactions of cyclohexane, as the simplest naphthene molecule available,
play important roles in determination of the high-temperature combustion behavior of the surrogate blends. Specifically important were the cascading dehydrogenation reactions of cyclohexane in prediction of ignition delay time data, and formation of the poly aromatic hydrocarbons. Due to this fact, in current research the cyclohexane will be replaced by propyl-cyclohexane, which has more complex molecular structure and larger size, and therefore is known as a more realistic substitution for naphthenic compound found in diesel blends. To this aim, the introduced surrogate formulas will be updated for high temperature ranges, and the corresponding kinetic model will be further extended, using the latest published naphthene sub-model. The simulation results will be compared with the experimental data, namely the high temperature ignition delay time and laminar flame speed data, as well as with the results of previous model. Since the performance of basis model was very consistent with ignition delay time data, the initial goal of this research is identified as repeating the same model response after substitution of propyl-cyclohexane. On this basis, a new surrogate formula will be introduced. Moreover, the appeared changes in prediction of laminar flame speed data will be in detailed discussed. At the end, the effective pathway toward formation of poly aromatic species will be investigated at the high emperatures.