Experimental Investigation of Flow Coking and Coke Deposition of Supercritical Hydrocarbon Fuels in Porous Media

Transpiration cooling technology is a feasible thermal protection method for hypersonic vehicles. To ensure the safety of transpiration cooling structures, the coke deposition rule of hydrocarbon fuels in porous media is a key problem that has to be considered. In this paper, experimental studies are reported on coke deposition of n-decane and HF-II fuel in sintered bronze porous media at different pressures and a temperature ranging from 350 to 638 °C. Results showed that the temperature was a dominant factor for coke generation from hydrocarbon fuels. Two types of coking behaviors, i.e., thermal-oxidative coking and pyrolysis coking, were observed, which resulted in the coke surface deposition rate exhibiting a double-peak curve. At a certain temperature, the mass flow rate determined the fluid residence time in porous channels. Thermal-oxidative coking was affected by the residence time and the dissolved oxygen concentration, so the coke surface deposition rate increased at first and then decreased wit...