Modeling the Thermodynamics of Oxygen-Enriched Combustion in a GE LM6000 Gas Turbine Using CH4/NH3 and CH4/H2

Gas turbines are widely used in power generation due to their reliability, flexibility, and high efficiency. As the energy sector transitions towards low-carbon alternatives, hydrogen and ammonia are emerging as promising fuels. This study investigates the thermodynamic and combustion performance of a GE LM6000 gas turbine fueled by methane/hydrogen and methane/ammonia fuel blends under varying levels of oxygen enrichment (21%, 30%, and 40% O2 by volume). Steady-state thermodynamic simulations were conducted using Aspen HYSYS, and combustion modeling was performed using ANSYS Chemkin-Pro, assuming a constant thermal input of 102 MW. Results show that increasing hydrogen content significantly raises flame temperature and burning velocity, whereas ammonia reduces both due to its lower reactivity. Net power output and thermal efficiency improved with higher fuel substitution, peaking at 43.46 MW and 42.7% for 100% NH3. However, NOx emissions increased with higher hydrogen content and oxygen enrichment, while NH3 blends exhibit more complex emission trends. The findings highlight the trade-offs between efficiency and emissions in future low-carbon gas turbine systems.