Differential Global Reaction Model with Variable StoichiometricCoefficients for Thermal Cracking of n ‑Decaneat Supercritical Pressures

This study presents a new modeling approach for the thermal cracking of hydrocarbon fuels at supercritical pressures. The thermal cracking process is treated as an infinite number of continuous microreactions at different fuel conversions, in which the stoichiometric coefficients of each species are expressed by continuous differentiable functions of the fuel conversion to consider the effects of secondary reactions. A set of thermal cracking experimental results involving n-decane was used as an example to show how to establish the differential global reaction (DGR) model with variable stoichiometric coefficients. The DGR model was implemented in a computational fluid dynamics simulation to predict n-decane thermal cracking coupled with flow, heat transfer, and wall thermal conduction. The results showed that the DGR model can more accurately predict the species mass fractions than existing global reaction models, especially for conditions when the secondary reactions strongly impact the thermal cracking...