Numerical investigation of the potential of using hydrogen as an alternative fuel in an industrial burner
Rashed Al-Ajmi, Abdulhafiz H. Qazak, Abdellatif M. Sadeq, Mohammed Al-Shaghdari, Samer F. Ahmed, Ahmad K. Sleiti
Abstract
This study investigates hydrogen and hydrogen-methane mixtures as alternative fuels for industrial burners, focusing on combustion dynamics, flame stability, and emissions. CFD simulations in ANSYS Fluent utilized the RANS framework with the k-ε turbulence model and the mixture fraction/PDF approach. Supporting Python scripts and Cantera-based kinetic modeling employing the GRI-Mech 3.0 mechanism and Zeldovich pathways analyzed equivalence ratios ( Φ ), adiabatic flame temperatures ( T ad ), and NO x formation mechanisms. Results revealed non-linear temperature trends, with a 50 % hydrogen blend yielding the lowest peak temperature (1880 K) and a 75 % hydrogen blend achieving optimal performance, balancing peak temperatures (∼1900 K), reduced NO x emissions (5.39 × 10 -6 ), and near-zero CO 2 emissions (0.137), though flame stability was impacted by rich mixtures. Pure hydrogen combustion produced the highest peak temperature (2080 K) and NO x emissions (3.82 × 10 -5 ), highlighting the need for NO x mitigation strategies. Mass flow rate (MFR) adjustments and excess air variation significantly influenced emissions, with a 25 % MFR increase reducing NO x to 2.8 × 10 -5 , while higher excess air (e.g., 30 %) raised NO x under lean conditions. Statistical analysis identified Φ , hydrogen content ( H 2 %), and flame stability as key factors, with 50 %–75 % hydrogen blends minimizing emissions and optimizing performance, emphasizing hydrogen’s potential with controlled MFR and air adjustments.