Effects of Pulsation Intensities on Flame Characteristics of a Small Backward-Inclined Jet Flame in Crossflow

Abstract
Abstract The effects of pulsation intensities on the flame characteristics of a 10 deg-backward-inclined jet flame in the crossflow were investigated in a wind tunnel. The jet and the crossflow Reynolds numbers were 1527 and 2165, respectively. The jet-to-crossflow momentum flux ratio was 0.10. A loudspeaker was used to acoustically excite the jet flame. The excitation Strouhal number was 0.73, while the jet pulsation intensities varied from 0 to 1.26. The flame behaviors were studied through photography techniques. The flame temperatures were measured using a fine-wire R-type thermocouple. The combustion-induced emissions were probed by a commercial multi-gas analyzer. The jet flames were categorized into five characteristic modes with increasing pulsation intensities. Mode I was characterized by a yellowish down-washed recirculation flame, a blue neck flame, and a yellow tail flame. Modes II and III featured a split yellow tail flame, a yellowish recirculation flame, and a blue neck flame. Mode IV was characterized by a blue down-washed recirculation flame and neck flame, as well as a split yellow tail flame. Mode V was identified by a single yellow tail flame and the absence of the down-washed recirculation flame. When the jet flames were excited beyond mode I, the combustion-induced pollutants of carbon monoxide and nitric oxide were significantly reduced. However, the excited jet flame in mode V displayed low temperatures in the near-tube region.

Citation
Hsu, C. M., Khan, F., & Mosiria, D. B. (2019). Effects of Pulsation Intensities on Flame Characteristics of a Small Backward-Inclined Jet Flame in Crossflow. Journal of Thermal Science and Engineering Applications, 12(2). doi:10.1115/1.4044166

Publisher
ASME International

Journal
Journal of Thermal Science and Engineering Applications

DOI
10.1115/1.4044166

Additional Links
https://asmedigitalcollection.asme.org/thermalscienceapplication/article/doi/10.1115/1.4044166/955317/Effects-of-Pulsation-Intensities-on-Flame

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