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arXiv · 2208.08890

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

Mohammadreza Sabzehali·Somayeh Davoodabadi Farahani·Amir Mosavi
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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 and on design. The results show that with a 20-degree delicious 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 percent, 16.51 percent, 11.76 percent, 10.53 percent, and 2.15 percent and SNOx and exergetic efficiency decrease by 2.11 percent and 26.60 percent, 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 the economic approach +18.89 percent, +10.01 percent, and -0.21percent, respectively, and based on the exero-environmental approach -54.03percent, -42.02percent, and +21.44percent change compared to the base engine, respectively.

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Mohammadreza Sabzehali, Somayeh Davoodabadi Farahani, Amir Mosavi. 2022-08-14. Energy-Exergy Analysis and Optimal Design of a Hydrogen Turbofan Engine. https://doi.org/10.31219/osf.io%2Fsu9pb

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