Energy-Exergy Analysis and Optimal Design of a Hydrogen Turbofan Engine

Abstract

In this study, the effect of inlet air cooling and fuel type on the performance parameters of thrust-specific fuel consumption (TSFC), thermal and exergetic efficiencies, entropy generation rate, and Nitrogen oxide emission intensity index (SNOx) of the GENX 1B70 engine is analyzed in two states of take-off. The results show that with a 20˚C reduction in inlet air temperature on design conditions and JP10 fuel usage, the thermal efficiency and entropy generation rate, thrust and fuel mass flow rate, and TSFC of the engine increase by 1.85, 16.51%, 11.76%, 10.53%, and 2.15% and SNOx & exergetic efficiency decrease by 2.11% and 26.60%, respectively. Also, optimization of the GENX 1B70 engine cycle as hydrogen fuel usage with three separate objective functions: thrust maximization, thermal efficiency maximization, and propulsive efficiency maximization on design point condition was performed based on the Genetic algorithm. Based on the economic approach and exero-environmental, the best cycles from the optimal states were selected using the TOPSIS algorithm. In on design conditions, entropy generation rate, nitrogen oxide production rate, and TSFC for the chosen cycle based on economic approach +18.89%, +10.01%, and -0.21%, respectively, and based on exero-environmental approach -54.03%, -42.02%, and +21.44% change compared to the base engine, respectively.