The size of the combustion space has a significant effect on the flame behavior in the micro combustor. In this paper, the structures and dynamics of laminar partially premixed methane/air were experimentally investigated as the combustion space gradually decreases. In the experiment, five flame regimes were observed in sequence: the stable flame, transient oscillating flame, extinction, flame with repetitive extinction and ignition (FREI), and quenching. The effects of the mixture flow rate, primary equivalence ratio, and separating distance of plates on the different flame behaviors were analyzed. It was revealed that increasing the mixture flow rate could improve the flame’s stability while increasing the primary premixed air, and the flame tended to become unstable. Moreover, in the FREI regime, the larger the separating distance, the lower the frequency of the FREI flame; meanwhile, the FREI frequency increased as the primary equivalent ratio decreased. The FREI frequency exhibited a non-monotonic change with the mixture flow rate and peaked at 1.06 m/s. Furthermore, it was demonstrated that the smaller the primary equivalent ratio, the smaller the quenching distance. The mixture flow rate had no significant effect on the quenching distance. The research is helpful to the design of the micro combustion device.

燃烧空间的大小对微型燃烧器中的火焰行为有重大影响。本文研究了随着燃烧空间逐渐减小，层流部分预混甲烷/空气的结构和动力学。在实验中，依次观察到五个火焰状态：稳定火焰，瞬态振荡火焰，熄灭，具有反复熄灭和点火的火焰（FREI）和淬火。分析了混合气流量，一次当量比和分离距离对不同火焰行为的影响。结果表明，增加混合气流量可以改善火焰的稳定性，同时增加一次预混空气，并且火焰趋于变得不稳定。此外，在FREI制度中，分隔距离越大，FREI火焰的频率越低；同时，FREI频率随着主要当量比的减小而增加。FREI频率随混合物流速显示出非单调变化，并达到1.06 m / s的峰值。此外，证明了一次当量比越小，淬灭距离越小。混合物流速对淬火距离没有显着影响。该研究有助于微燃烧装置的设计。混合物流速对淬火距离没有显着影响。该研究有助于微燃烧装置的设计。混合物流速对淬火距离没有显着影响。该研究有助于微燃烧装置的设计。