INVESTIGATIONS ON LEAN TURBULENT PREMIXED HYDROGENATED FLAMES

Hydrogen's ability to enhance carbon neutrality in combustion processes puts forward the use of hydrogenated fuels. However, hydrogen alters the flame structure by reducing flame thicknesses and heights while raising the flame temperature. Optimizing lean premixed flames is also an approach for achieving efficient and cleaner combustion. Yet, lean premixed flames are prone to instabilities, hence when combined with hydrogen addition, determining the instability limits is crucial. These factors all indicate that hydrogenated fuels should be researched as potential fuels for lean premixed combustion in the future. In this study, lean premixed turbulent flames of hydrogenated conical methane-air mixtures are investigated experimentally in a high-pressure combustion chamber, Lean methane-air premixed flames with varying hydrogen addition rates up to 20% are investigated with chemiluminescence measurements of OH and CH radicals and Mie scattering. The data is used for investigating the characteristics of the turbulent flame front dynamics.