Conjugate heat transfer analysis of a ram/scramjet with thermal decomposition of the regenerative cooling channel

This study conducts a conjugate heat transfer (CHT) analysis to design the regenerative cooling system of a dual-mode ram/scramjet aircraft operating in a flight environment. The analysis incorporates key factors such as heat generation from airflow, temperature variations due to structural material, and the properties of supercritical fuel within the cooling channels. The cooling channel analysis part introduces a temperature correction method for efficient supercritical flow simulation. The CHT methodology was validated through comparisons with experimental data, focusing on aerodynamic heating, structural thermal responses, and cooling channel performance. The analysis also includes the prediction of supercritical fuel properties, specifically the thermal decomposition of JP-10 fuel, which is characterized by a high critical compressibility factor ($Z_c$). By implementing a method that resolves instability in property predictions, a stable CHT analysis framework was established. This approach enables detailed investigation of thermal behaviors related to fuel flow within cooling channels. Furthermore, the application of a reliable predictive method for both the aircraft’s flight environment and the characteristics of fuels with high $Z_c$ extends the range of fuels that can be considered in CHT analyses. This study contributes to advancing the design and performance evaluation of regenerative cooling systems in high-speed aerospace applications.