To support aviation decarbonization and improve overall propulsion efficiency,
this paper proposes a hybrid propulsion architecture integrating a proton
exchange membrane fuel cell (PEMFC) with a turbofan engine. The proposed
parallel hybrid configuration achieves efficient energy conversion through the
thermodynamic coupling of key components, including the heat exchanger, ducted
fan, compressor, and combustor. A thermodynamic model is developed for parameter
matching and system analysis. Results indicate that, at the design point, the
overall system efficiency reaches 0.36, with a thermal efficiency of 0.42 and a
propulsive efficiency of 0.82. Compared with the baseline CFM56-3C1 engine, the
proposed system shows improved fuel economy and environmental performance,
achieving a specific fuel consumption of 5.8 g/(s·kN), NOx emissions of 0.0063
g/kg-fuel, and a noise level of 92 dB. Exergy analysis further indicates that
the primary exergy destruction occurs within the fuel cell (20%) and during
combustor heat transfer (18%). These findings suggest that multi-energy pathway
coupling can reduce fuel consumption and emissions, providing a potential
approach for low-carbon aviation propulsion systems.