RT Journal Article ID 01aff8da7de13019 A1 Inamura, Takao A1 Yanaoka, Hideki A1 Kawada, Takaaki T1 VISUALIZATION OF AIRFLOW AROUND A SINGLE DROPLET DEFORMED IN AN AIRSTREAM JF Atomization and Sprays JO AAS YR 2009 FD 2009-07-31 VO 19 IS 7 SP 667 OP 677 AB A droplet in an airstream deforms and disintegrates into finer droplets by a complicated mechanism. We focus on bag-type and umbrella-type breakup mechanisms in the present study. Under conditions in which the relative velocity between a droplet and the airstream is low, the droplet breakup mechanism changes from bag-type to umbrella-type breakup with a small increase in the relative velocity. The airflow around a single deformed droplet was visualized and the velocity distributions were measured by particle image velocimetry. The droplet velocity was measured by high-speed video. The experimental results show that vortices are generated on the leeward side of the droplet. For the bag-type breakup, the vortices are generated alternately, similar to a Karman vortex. For the bag-type breakup, the upward air velocity toward the leeward surface of a droplet is less than the downward air velocity toward the windward surface. The relative velocity between the upward and downward air velocities bulges the droplet out like a bag. On the other hand, for the umbrella-type breakup, bilaterally symmetrical twin vortices are generated. The upward velocity is almost the same as the downward velocity. Therefore, the center of the droplet remains as a wick and the peripheral part of the droplet bulges out. PB Begell House LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,0d19acee1c90fd46,01aff8da7de13019.html