effects of syngas h2/co composition and turbulent intensity on the bluff-body premixed combustion characteristics

The effects of hydrogen content variation in h2/co composition with different turbulent intensities were numerically investigated. the gri3.0 reduced mechanism, including 15 species and 46 subreactions with scale-adaptive simulation (sas) turbulence model and eddy-dissipation concept (edc) turbulence-chemistry interaction, was utilized in fluent. in lean combustion, by increasing hydrogen content, the production of oh  radicals is increased, and they consume co  drastically, leading to a high co  consumption rate. in rich combustion, as hydrogen concentration rises, oh  and o radicals tend to react with hydrogen instead of co  due to hydrogen's higher reactivity, decreasing co  the consumption rate. with hydrogen concentration enhancement, the amount of vapor products rises, causing the products' heat capacity to increase. then, the produced combustion heat, flame temperature, and produced no  gases are decreased. the maximum flame temperature no  occurs at the equivalence ratios of 1.1 and 0.9, respectively, from kinetics analysis. based on the sensitivity analysis, no the production rate is limited by o radicals. at the same time, maximum no  occurs at equivalence ratio one from the cfd result due to the higher residence time caused by the burner geometry. the enhancement of turbulence intensity leads to high residence time, intensifying the flame and resulting in a lower lean blowout limit.