Structure and stabilization mechanism of a microjet methane diffusion flame near extinction,” in

The advances in MEMS fabrication technologies have led to intensive research interest in high-density and long-operation micro-power generation devices as an alternative power source for numerous applications1. With a energy density of about 100 times higher than that of the most advanced batteries, a micro-scale hydrocarbon combustion system has been considered as a viable alternative to batteries. Therefore, an understanding of the physics and chemistry of the laminar microjet flame is of vital importance. Due to its small size, the amount of heat released from the flame is very small, whereas the heat loss to the burner would be relatively large. This indicates that the flame might be always operated in a severe condition especially near extinction limit. Experimental measurements have shown that the imaged flame shapes of microjet methane diffusion flames are completely different between the direct photograph and laser shadowgraph2. This fact implies that an intensive characteristic hot region may exist just ahead of the flame zone. Several issues3,4 concerning the structure and stabilizatio