Thermal response modeling and analysis of hydrocarbon fuel transient flow and heat transfer at supercritical pressure

The demands for wider speed range and longer endurance of hypersonic vehicles make the flight state transition an issue to be considered. To get a fundamental understanding of the thermal response characteristics of supercritical fuel under varying operation conditions, a series of experimental and numerical studies have been conducted in this research. The effects of different operation parameters on the response time have also been investigated. The research revealed that when the temperature is below the pseudo-critical temperature, the thermal response time decreases with the increase of temperature. Additionally, the results have shown that the mass flow rate increase leads to the decrease of thermal response time decreases in the same temperature range. The effect of pressure is most notable near the pseudo-critical temperature due to the drastic change of physical properties near the pseudo-critical temperature. The effect of the solid domain on the response time is accomplished through the thermal conduction in the solid domain, and a thicker wall thickness and higher thermal inertia of the tube lead to a longer response time. An empirical correlation based on the experimental data has been proposed to predict the thermal response time. These results provide a reference for cooling channel design and coolant management.