Atomization Experiments in a Coaxial Coflowing Mach 1.5 Flow
Extensive flow visualization using schlieren/shadowgraph, flash photography and short duration (ns) laser imaging, and drop size measurements are reported in this work. The supersonic nozzle operating conditions ranged from an overexpanded to highly underexpanded mode. A phenomenon of the liquid jet expanding into a bubblelike formation as it interacts with the first set of waves is explained. Photographic evidence indicated the presence of a primary region enclosed by the first shock cell where the primary breakup occurred, a secondary region enclosing the bubblelike formation, and a third subsonic region further downstream. Atomization seemed to be initiated by the growth of three-dimensional structures on the liquid surface. Subsequent detachment of the three-dimensional structure as fine droplets by the intense shear at the liquid gas interface was observed. This seems to partially confirm the boundary-layer stripping mechanism proposed by Taylor and Ranger and Nicholls.
K. M. Isaac et al., "Atomization Experiments in a Coaxial Coflowing Mach 1.5 Flow," AIAA Journal, American Institute of Aeronautics and Astronautics (AIAA), Jan 1994.
The definitive version is available at http://dx.doi.org/10.2514/3.12154
Mechanical and Aerospace Engineering
Article - Journal
© 1994 American Institute of Aeronautics and Astronautics (AIAA), All rights reserved.