A Surface Analysis-Based Investigation of the Effect of Wall Materials on Flame Quenching

Abstract

An investigation of a premixed methane-air flame was conducted with a slit burner between two parallel walls to examine the effects of wall material and temperature on flame quenching. Three different materials (i.e., zirconia ceramics, stainless steel 304, and Si) were tested at wall temperatures of 100–700°C. The quenching distances for the three wall materials at the same temperature decrease in the order stainless steel 304 > Si > zirconia ceramics. For all materials, the quenching distance shortens with increasing wall temperature. To clarify the differences among the materials, the surface structure and composition of the raw and used walls were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The results show that the percentages of chemisorbed oxygen on the surfaces decrease in the order zirconia ceramics > Si > stainless steel 304—a behavior that can be correlated with the order of quenching distances of the three wall materials, which moves from small to large. In short, the higher the percentage of chemisorbed oxygen, the shorter the quenching distances.

Keywords:

• Chemical quenching
• Chemisorbed oxygen
• Flame quenching
• Quenching distance
• Surface analysis

ACKNOWLEDGMENTS

The present work was supported by National Science Foundation of China under grant No. 50776090 and by Strategic China–Japan Joint Research Program of NSFC-JST under grant No. 50721140651.

Notes

Note. O_I = lattice oxygen; O_II = chemisorbed oxygen; O_T = total oxygen; A_T = all atoms.

Note. *denotes a vacant surface site and H*denotes the adsorbed surface species.