Numerical simulation of industrial gas burners fueled with hydrogen-methane mixtures for enhanced combustion efficiency and reduced greenhouse gas emissions

In this study, the performance of gas burners fueled with mixtures of methane, hydrogen, and air was investigated numerically using ANSYS Fluent V22. The objective is to analyze the effect of hydrogen mass fraction on gas burner performance. A numerical domain was defined to simulate the combustion process and evaluate various parameters. The burner was operated under steady conditions with fuel blends consisting of different hydrogen fractions (25%, 50%, and 75%) mixed with methane. The simulation utilized a non-premixed model with flamelets to capture the combustion behavior. Several important parameters were determined, including methane and hydrogen mass fractions, combustion temperature, turbulence intensity, and mass fraction variance. Additionally, the distribution of major pollutants such as CO and CO2 were calculated throughout the simulation domain. The findings revealed that hydrogen exhibits faster and easier combustion due to its higher flame speed and lower ignition temperature. The addition of hydrogen as a secondary gas with methane resulted in increased combustion temperature. A higher hydrogen content in the fuel blend led to a lower mass mixing fraction, indicating more complete fuel combustion. Moreover, the presence of hydrogen enhanced the turbulence intensity and turbulence kinetic energy. On the other hand, incomplete combustion of methane contributed to increased CO formation. An important observation is that the combustion of hydrogen did not produce CO2 emissions, unlike methane and other hydrocarbon fuels. Therefore, optimizing the combustion process, improving burner efficiency, and utilizing cleaner fuels such as hydrogen present potential strategies for reducing CO2 emissions. Additionally, hydrogen indicated the enhanced combustion efficiency across all operating conditions. These findings highlight the advantages of hydrogen as a fuel source, emphasizing its favorable combustion characteristics and reduced environmental impact. By leveraging these benefits and refining the combustion process, it is possible to achieve more efficient and environmentally friendly gas burner systems.