Analysis of overall performance and matching mechanism of a novel hydrogen mixed-flow turbofan hybrid electric propulsion system

Supersonic civil aircraft has received increasing attention in recent years due to its wide range of application potential. However, existing propulsion cycle schemes lead to significant challenges in meeting the performance requirements of supersonic civil aircraft, stemming from the inability to balance the conflicting cycle parameter requirements of high-speed and low-speed operations. This study proposes a novel hybrid propulsion system for supersonic civil aircraft based on a mixed-flow turbofan engine with integrated hydrogen energy, intercooled heat transfer and high-temperature fuel cells, develops a performance simulation model to analyse the matching mechanism of this new thermal-electric coupled cycle. The propulsion cycle combines the advantages of conventional gas turbine and electric propulsion to achieve high efficiency and sufficient thrust over a wide speed range from Mach 0 to 3. The intercooler module mitigates the problem of overrun of the compressor outlet temperature, and the thermoelectric coupling design also mitigates the high aerodynamic and thermal loads of the engine hot-end components under the high-power demand condition and reduces the difficulty of designing the hot-end components. Results show that under the same design parameters, compared with the conventional scheme, the proposed coupled propulsion cycle scheme increases the thrust by 29.06 % and reduces the fuel consumption rate by 11.66 % in the maximum flight speed condition, and the maximum flight speed is increased from Mach 2.8 to Mach 3.1. At the same time, the propulsion scheme achieves the goal of constant-mass-flow throttling of the propulsion system without relying on complex adjustable geometries.