Simulating natural gas combustion with steam injection to reduce NOx emissions

NOx emissions from combustion processes pose significant environmental challenges. In response, researchers worldwide are investigating methods to reduce these pollutants. This paper explores the effectiveness of steam injection in reducing NOx emissions through numerical simulations of a diffusion-type combustion process in a gas turbine combustion chamber. In this study, steam and methane are premixed and then introduced into the combustion chamber through parallel inlets along with air. Key parameters such as boundary conditions, wall conditions, and flow rates are meticulously defined. The simulations are performed using ANSYS Fluent software, with validation against experimental data to ensure accuracy. After validation, various steam mass fractions, specifically 0%, 10%, 20%, and 30% H 2 O by mass fraction relative to methane, are examined for their impact. The simulation results, including temperature, carbon monoxide, and NOx concentrations, are compared across different steam mass fractions. The simulation results show that increasing the steam fraction from 10% to 30% relative to methane reduces NOx emissions from 7 ppm to 0.12 ppm at a radial distance of 4 cm, demonstrating a significant NOx reduction effect through steam injection. The findings indicate that increasing the steam mass fraction reduces NOx emissions, demonstrating the potential of this method for cleaner combustion processes.