Performance analysis and economic evaluation of the ammonia decomposition turbine-less SOFC/supersonic jet engine hybrid system

Abstract To address the issues of severe noise pollution and high carbon emissions associated with turbine engine propulsion systems used in previous generations of supersonic technology, this study proposes the ammonia decomposition turbine-less SOFC/supersonic jet engine hybrid system (NH 3 SOFC/SJE system). The proposed design aims to achieve supersonic cruising, transoceanic flight, and zero-carbon emissions, offering a sustainable solution for next-generation supersonic propulsion systems. The results indicate that as the pressure ratio increases, specific thrust continues to rise, while the fuel consumption rate initially decreases and then increases. The optimal pressure ratio is found to lie between 15.1 and 19.8. Higher fuel utilization efficiency contributes to the improved performance of the hybrid system. When the ammonia decomposition temperature is around 900 K, both the fuel economy and propulsion performance of the hybrid system are effectively met. The hybrid system achieves the most economical cruising state at an altitude of 20 km and a Mach number of 1.8. In this optimal cruising state, the Cost per unit distance of the conventional turbojet engine is 39.9% higher, while that of the H 2 SOFC/SJE system is 6.03% higher compared to the proposed system. In summary, ammonia, as a zero-carbon fuel, offers significant advantages for supersonic flight.