Flashback behavior and safety implications of hydrogen–natural gas mixtures

Hydrogen blending in natural gas systems is a key transitional strategy for reducing carbon emissions. This study explores the influence of hydrogen on combustion properties, including flame flashback risk, quenching distance, and energy efficiency. Experimental and computational analyses demonstrate that hydrogen addition increases flame speed but reduces calorific value and quenching distance, thereby impacting combustion stability and safety. Findings suggest that optimizing burner design and combustion control strategies is essential for safely and efficiently using hydrogen-enriched natural gas. Experimental validation confirmed that a 1.50 mm channel dimension effectively prevented flame flashback for hydrogen concentrations up to 40% in natural gas. As energy systems evolve toward decarbonization, this research provides critical insights into the feasibility and challenges of hydrogen integration in residential or industrial applications. The study investigated the combustion behavior of natural gas enriched with various concentrations of hydrogen (up to 25%). Dynamic or fluctuating mixing conditions were excluded, as the implementation of such a system in energy sector applications would necessitate a stable and well-defined gas composition.