Heat transfer characteristics of kerosene phase change based on fuel flow rates in the regenerative cooling heat exchanger of scramjet engines

In this study, we investigated the heat transfer characteristics of kerosene for various fuel flow rates in the regenerative cooling heat exchanger of scramjet engines. We used hydrogen for combustion and kerosene for the heat exchanger regenerative cooling. The internal combustor wall surface temperature was measured using a phosphor thermometer. The fuel pressure and temperature were also measured. Significant changes were observed when kerosene flow rate changed from 6 to 8 g/s. The fuel boiling point at specific pressures and temperatures was obtained using differential scanning calorimetry; at the kerosene boiling point, they were found to be consistent with the temperature and pressure values between 6 and 8 g/s fuel flows, which confirmed that the fuel changes from liquid to gas under these circumstances, leading to considerable changes in the surface and fuel temperature tendencies. These findings could help in the optimal design of scramjet engines regenerative cooling heat exchangers.