Design and heat transfer characteristics analysis of combined active and passive thermal protection system for hydrogen fueled scramjet

Many methods have been widely carried out to develop the thermal protection system of hydrogen fueled scramjet to meet the cooling requirements of engine. A combined thermal protection system is designed and developed by combing active and passive thermal protection systems and proposed to endure the long duration safe operation of a scramjet at high flight Mach number. The combined thermal protection system proposed is designed in the light of the dangerous conditions for an active thermal protection system, and its performance is evaluated with a one-dimensional coupled heat transfer model of a hydrogen fueled scramjet at different Mach numbers and equivalence ratios. Test results indicate that the thermal protection system proposed could be used to expand the flight range of a scramjet by properly selecting conductivity and thickness of passive layer.