A Numerical Study on Endothermic Chemical Reactions of Supercritical n-dodecane in a Regenerative Cooling Channel of Hypersonic Vehicles

A numerical study has been conducted on the endothermic decomposition reactions of n-dodecane in a regenerative cooling channel by using a multi-step PPD (Proportional Product Distribution) model in order to develop a practical numerical simulation technique for analyzing and designing an active regenerative cooling system of hypersonic cruise vehicles. The PPD model includes the primary cracking which is applicable up to the fuel conversion rate of 13% while the secondary cracking which should be incorporated for the conversion rate of above 13%. Results for both the primary and secondary cracking regions show that the fuel outlet temperature is lower when the thermal cracking is considered due to the endothermic nature of the reaction. Furthermore, the predicted distributions of major gaseous and liquid products with respect to the fuel conversion rate agree very nicely with existing numerical and experimental data, which confirms the validity of the numerical technique applied in the current study.