A LOW-IMPACT HIGH-EFFICIENCY BRAYTON CYCLE CONCEPT WITH EVAPORATIVE COOLING DURING THE COMPRESSION PROCESS USING H2/CH4 FUEL BLENDS
DOI:
https://doi.org/10.59277/CLC.2024.37Keywords:
Evaporative cooling, Hydrogen, Brayton cycle, Entropy generation, Constructal LawAbstract
Towards a low-impact, high-efficiency Brayton cycle concept, a gas generator system including a compressor with evaporative cooling, a combustion chamber using H2/CH4 fuel blends, and a gas turbine is being analyzed at this preliminary stage. The Constructal approach on the effectiveness of compressed air temperature control by evaporative cooling, previously carried out by the authors, shed some light on the potential growth of mechanical power provided by gas turbine power plants of 45.81% and a simultaneous reduction of 2.26% in specific fuel consumption.
The current study carried out on the combustion chamber reveals that increasing the H2 fraction in the fuel blend results in a direct reduction in carbon dioxide production and a decrease in CO and NOx emissions when the temperature of the flue gas is maintained at 1450 K. Meanwhile, the exergy efficiency of the combustion chamber remains almost constant at 39.3%. Studying the two components already analyzed, the compressor and the combustion chamber, allows us to move towards a low-impact, high-efficiency Brayton cycle concept as close as possible to its technical implementation.
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