Abstract
A micro laminar premixed flame stabilized by an annular pilot flame is observed. The flame is formed even on a burner whose diameter is 0.3 mm. However, the shape of the flame formed on the burner whose diameter is less than 1mm and at around the lowermost flow rate is nearly spherical. It is similar to the appearance of a micro diffusion flame. The flame formed on the burner which has a diameter less than 1 mm is not considered a propagating flame, because a typical laminar propagating flame has a structure thickness that is more than 0.5 mm. The flame structure variation and the uppermost and the lowermost flow rates that the flame could be formed stably were observed. Consequently, it is supposed that the flame formed on a burner with a submillimeter diameter is dominated by the diffusion mixing of oxygen and methane from the main premixture flow, and heat and radicals from the pilot flow. The extinction mechanism of the micro premixed flame was examined and the scale effect on the extinction limit and the flame structure were considered.
