Flow, combustion and species fields of premixed CH₄/H₂/CO syngas oxy-flames on a swirl burner: Effects of syngas composition

Addressing burning characteristics of syngas under oxy-combustion conditions in substantially CO₂-diluted combustion environment for gas turbine combustion applications has rarely been reported. A detailed modeling study was performed over a broad range of syngas compositions at fixed inlet flow velocity of 6 m/s, fixed equivalence ratio of 0.42, and fixed oxygen fraction (OF) of 60% (by vol.). For validating the numerical model, the calculated results were compared against experimental results recorded from the same physical combustion setup. The effects of syngas composition on flow field, laminar flame speed (LFS), flame thickness, adiabatic flame temperature (AFT), combustor power density (PD), thermal power (TP), and species distributions were investigated. Adiabatic flame temperature increased from 2312 to 2388 K, LFS increased from 0.53 to 1.32 m/s, PD reduced from 2854 to 2672 kW/m³, and TP decreased from 4.0 to 3.7 kW when the hydrogen fraction (HF) was changed from 0 to 80%.When the HF was reduced from 90% to 10%, with excluding CH₄, the AFT increased from 2447 to 2560 K, the LFS decreased from 2.01 to 0.46 m/s, the TP increased from 3.64 to 4.1 kW, and the PD increased from 2620 to 2923 kw/m³.