Thermal Management of Hydrocarbon Fuels in Hypersonic Applications

Hypersonic vehicles travelling at speeds above Mach 5 encounter extreme aerodynamic heating, necessitating advanced thermal management to protect structural and propulsion systems. Hydrocarbon fuels offer a dual function as both propellant and coolant via regenerative cooling, in which fuel is circulated through engine walls or heat exchangers to absorb heat before combustion. Under increasing pressure and temperature, these fuels reach supercritical states, enhancing heat transfer but also triggering endothermic cracking reactions that further increase heat sink capacity. However, fuel decomposition can lead to coke deposition, impairing flow passages and heat exchange surfaces. Recent efforts focus on understanding coupled heat-transfer and chemical-kinetic processes, developing catalysts or initiators to promote low-temperature cracking, and designing channel geometries or surface coatings to suppress coking while optimising heat absorption. Integrating numerical simulation, high-pressure experiments and materials science has yielded a more predictive framework for fuel-coolant behaviour, supporting the global drive towards reusable high-speed flight and rapid response aerospace platforms.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Thermal Management of Hydrocarbon Fuels in Hypersonic Applications publication trend

The graph below shows the total number of articles in thermal management of hydrocarbon fuels in hypersonic applications across all publications each year (not limited to Nature Index journals).

Technical terms

Regenerative cooling: A technique in which fuel circulates through or around engine components to absorb heat before combustion, serving as both coolant and propellant.

Supercritical condition: A fluid state above its critical temperature and pressure, exhibiting enhanced heat-transfer properties and continuous phase characteristics.

Endothermic cracking: Thermal decomposition of hydrocarbon molecules that absorbs heat, increasing the total heat sink capacity of the fuel.

Heat sink capacity: The amount of thermal energy a fuel can absorb through sensible heating and endothermic reactions per unit mass.

Coke deposition: Formation of solid carbonaceous residues on surfaces due to fuel cracking, leading to flow blockage and reduced heat-exchange efficiency.

Pyrolysis: High-temperature chemical breakdown of hydrocarbons in the absence of oxygen, producing smaller hydrocarbons, hydrogen and coke precursors.

References

1. Numerical Study on Flow and Heat Transfer of Supercritical Hydrocarbon Fuel in Curved Cooling Channel. Applied Sciences (2022).
2. Research Progress of Catalysts and Initiators for Promoting the Cracking of Endothermic Hydrocarbon Fuels. Transactions of Tianjin University (2022).
3. Progress of Coupled Heat Transfer Mechanisms of Regenerative Cooling System in a Scramjet. Energies (2023).