Experimental study of syngas combustion on a novel swirl multi-nozzle micromix combustor

In this paper, a novel swirl multi-nozzle micromix combustor has been designed for the Integrated Gasification Combined Cycle (IGCC) gas turbine. The flame structure within the equivalence ratio of 0.3-0.9 and air flow speed of 30-80 m/s was captured with OH* chemiluminescence measurements at atmospheric pressure and high air temperature (-691 K). The flame structure characteristics were investigated and an intrinsic link between flame structure and stability was established. The results show that the peak flame axial OH* intensity was 1.44D-1.89D from the nozzle exit. When the equivalence ratio increases, the single micromix flame transitions from a V-shaped (on the verge of blowing out) to an attached M-shaped (on the verge of flashback) flame, and the equivalence ratio of the transition increases with the flow rate increases. The flames were categorized into four characteristic structures, of which the corner flame morphology is an important basis for determining stability.