Flame Diagnostics: Local Temperature Profiles and Atomic Fluorescence Intensity Profiles in Air-Acetylene Flames

Abstract

Temperature profiles of the “premixed” air-acetylene and argon-separated air-acetylene flames, produced with a capillary burner, have been investigated by a two-line atomic fluorescence method. The temperatures were obtained at a volume resolution of 0.3 × 2 × 5 mm3 in the flames. In an unseparated air-acetylene flame, temperature ranges from ca. 2600 to ca. 1900°K; the highest temperature (2650°K) was found 3 mm from the burner center and 60 mm above the burner head. In an argon-separated air-acetylene flame, temperature is in the range ca. 2500 to 1300°K; the temperature is the highest at the center and decreases rapidly towards the fringe of the flame (outer cone) due to the cooling effect of argon gas. In order to elucidate the analytical usefulness of the temperature profiles obtained, atomic fluorescence intensity profiles of Mg, Cu, In, and Cr have been also measured and discussed in detail.