The Effect of Gravity on Premixed Flame Propagation and Extinction in a Vertical Standard Flammability TubeThe effect of gravity on the upward and downward flame propagation in lean methane/air and lean propane/air mixtures was studied using plexiglass flammability tubes with ignition at the open-end gravity levels which ranged from microgravity (0 + or - 0.1 g) to 1.77 g. The lean limits were found to be about 5.25, 5.25, and 5.85 percent methane in air; and about 2.15, 2.06, and 2.20 percent propane in air for 1 g upward propagation, 0 g, and 1 g downward propagation, respectively. The propane/air flames observed were stable, irrespective of the g level. On the other hand, lean methane/air flames were found to be sporadically unstable for upward propagation at g levels less than 0.5 g, and for donward propagation at g = 1.0. The extinction process observed was the same for both systems studied: at g = 0, the flame extinguished from the edge toward the center, while at g of 1 and above, the flame extinguished from the center toward the edge.
Document ID
19880051305
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Strehlow, Roger A. (Illinois Univ. Urbana, IL, United States)
Noe, Kurt A. (Illinois Univ. Urbana, IL, United States)
Wherley, Brian L. (Illinois, University Urbana, United States)