Combined CFD and Field Study of Hydrogen-Supplemented Natural Gas Combustion in Gas Turbines

Abstract

The transition toward low-carbon energy systems has accelerated research on alternative fuels that can be integrated into existing power generation technologies. Hydrogen has emerged as a promising energy carrier due to its high energy density and carbon-free combustion characteristics. Gas turbines, widely used in large-scale electricity production, offer significant potential for partial substitution of natural gas with hydrogen. In this context, the present study investigates the combustion behavior and emission characteristics of hydrogen-enriched natural gas in an annular gas turbine combustion chamber using computational fluid dynamics (CFD). A three-dimensional combustor model was developed using SolidWorks and imported into ANSYS Fluent for numerical simulations. The analysis was performed under non-premixed combustion conditions using real operational data obtained from industrial gas turbine units to define the boundary conditions. In the simulation, natural gas was supplied through the premix line while hydrogen was introduced through the pilot line. The fuel mixture consisted of 92% methane and 8% hydrogen by mass. Key combustion parameters, including temperature distribution, flow velocity, pressure characteristics, turbulence intensity, and pollutant emissions, were evaluated to assess the effects of hydrogen enrichment. The simulation results indicate that the addition of hydrogen significantly influences the combustion process by increasing flame temperature and enhancing combustion efficiency. The maximum combustion temperature in the chamber increased compared with conventional natural gas operation. More importantly, pollutant emissions were considerably reduced. The predicted nitrogen oxide (NOx) and carbon monoxide (CO) concentrations were substantially lower than those typically observed in natural gas–only combustion systems. Overall, the findings demonstrate that moderate hydrogen blending in natural gas-fired gas turbines can improve environmental performance while maintaining stable combustion characteristics. The results highlight the potential of hydrogen-enriched combustion as a practical approach for reducing emissions in existing gas turbine power plants without requiring extensive modifications to the combustion system.