A reduced chemical kinetic mechanism for diesel/biodiesel surrogate fuel: Formulation and validation

The development of accurate and reliable combustion kinetic models is imperative to advance the application of diesel/biodiesel blended fuels in marine engines. This study developed a reduced kinetic mechanism comprising six surrogate components (n-hexadecane, 2-methylheptane, methylcyclohexane, n-propyl benzene, methyl decanoate, and methyl-9-decenoate) based on the decoupling method. The mechanism encompasses the critical pathways from the oxidation of the components to the formation of polycyclic aromatic hydrocarbons, consisting of 129 species and 400 reactions. To comprehensively evaluate its performance, rigorous validations of the mechanism were conducted against multi-scale experimental data, spanning the fundamental combustion properties of the surrogate components, the spray combustion characteristics of diesel/biodiesel obtained in a constant volume combustion chamber, and the ignition and heat release processes of the blended fuel in a practical marine engine. The comparisons indicate that the proposed mechanism reproduces well the experimental results across various conditions, confirming the capability of the developed multi-component mechanism to support in-depth analysis and optimization of heat release process for biodiesel/diesel blended fuel in marine engines.