Comparative performance analysis of solid oxide fuel cell turbine-less jet engines for electric propulsion airplanes: Application of alternative fuel

摘要

Technology progress makes it possible to power airplanes by fuel-flexible and highly efficient solid oxide fuel cells (SOFCs). A turbine-less jet engine is achieved by integrating SOFCs with a compressor and a nozzle. It can be applied to electric propulsion airplanes. The compressor is powered by SOFCs instead of turbines. However, it is uncertain which type of fuel is suitable to the SOFC jet engine because the propulsion system is sensitive to performance and weight. In this paper, preliminary thermodynamic cycle analysis shows that fuel types and pressure ratios are key parameters for the engine. Then, five configurations of the SOFC jet engines when fed by hydrogen, methane, methanol, decane and propane are proposed and comparative performance analysis is accomplished. Main conclusions are as follows: (1) The specific thrust of the engine is nearly regardless of fuel types, which is about 970-1000 N/(kgs(-1)). The thermal efficiency and the specific impulse of the engine both decrease when methane is replaced by propane or decane. (2) The differences of performance resulting from fuel types increase with the increase of pressure ratios. (3) At the fuel-air equivalent of 1, the specific impulse of the engine fed by methanol is low to 1209 s. (C) 2019 Elsevier Masson SAS. All rights reserved.