Forced Convective Heat Transfer of RP-3 Kerosene at Supercritical Pressure inside a Miniature Tube

Abstract

In order to obtain heat transfer characteristics of RP-3 kerosene flowing in cooling channels of scramjet under supercritical pressure, experiments on heat transfer to RP-3 kerosene flowing in a miniature tube are conducted. The experimental parameters are as follows, heat flux varies from 0.3MW/m2 to 0.5MW/m2, mass flow rate is 1.3g/s, pressure is 5MPa and fluid temperature is from 20°C to 550°C. Results indicate that there are three regimes for heat transfer of RP-3 kerosene under supercritical pressure, namely the common heat transfer, the enhanced heat transfer and the deteriorated heat transfer. When bulk temperature is from 20°C to 275°C, it is common heat transfer regime. Heat transfer coefficient increases with bulk temperature, but the increment is relatively small. Enhanced heat transfer regime is from 275°C to 500°C. Heat transfer coefficient increases much more rapidly with bulk temperature and reaches relatively high value. Deteriorated heat transfer regime is from 500°C to 550°C. Heat transfer coefficient decreases when bulk temperature increases. Mechanism of these three regimes are analyzed. Variations of properties and laminar flow are responsible for common heat transfer. Turbulence is the main reason for enhanced heat transfer. Heat release reactions (combination of small molecules into big molecules) are attributed to the heat transfer deterioration.