Performance evaluation of the precooled jet engine with solid oxide fuel cell driven compressor for supersonic transport

For supersonic transport aircraft, conventional turbine engines fail to balance cruise performance, cost, and emissions. The jet engines that employ electricity instead of turbines to drive compressors present a promising propulsion scheme, but the high temperature of incoming airflow at high Mach number makes it difficult to operate safely. This study presents a precooled jet engine with solid oxide fuel cell (SOFC) driven compressor (PJEF), integrating precooling technology for stable high-speed flight. A model is developed to evaluate system performance, focusing on key factors such as fuel partition, anode recirculation, and precooled process. Sensitivity analysis is conducted on component efficiencies. The results demonstrate that liquid methane, as an alternative fuel, exhibits the optimal comprehensive performance. Compared to precooled turbojet engines (PTJE), the PJEF achieves an 10.12 % increase in specific thrust and specific impulse, a 5.68 %–9.69 % improvement in thermal efficiency, and a 2.89 %–3.23 % boost in overall efficiency at Mach 3. Furthermore, optimized fuel partition and anode recirculation ratios can notably enhance SOFC power density, while the precooling depth must balance compressor inlet temperature and fuel consumption. Besides, sensitivity analysis reveals that compressor efficiency most critically affects specific thrust, warranting prioritized optimization. This study provides key insights for next-generation supersonic propulsion development.