The Visible Structure of Turbulent Jet Diffusion Flames: Large-Scale Organization and Flame Tip Oscillation

摘要: Abstract High speed visual observations of free turbulent jet diffusion flames are presented. Computer graphic volume rendering, whereby many frames from a movie sequence displayed simultaneously, is used to provide unique view the flow evolution. Two fuels were used, acetylene and ethylene, span Ihe range momentum-driven buoyancy-driven regime. The data show that, for all regimes, exhibit large-scale organized motion in far-field as manifested by progression structures up through length visible flame. Occasional pairings also observed. These eventually become flame tip, which burns out quasi-periodic manner. Under no conditions was random, small-scale breakup disappearance tip ever In cases structure seen be constant equal 12 ± 2° exit velocity. constancy occurs spite axial de...