Experimental Investigation of Droplet Breakup at Constant Weber Number in Sub- and Supersonic Flows

This study experimentally investigates the effect of the freestream Mach number (M∞) on the droplet stripping breakup. Millimeter-sized ethylene glycol droplets are exposed to gas flows in a shock tube, and the breakup process is captured by an ultra-high-speed camera in combination with a Schlieren system. The flow conditions are maintained at We ~ 1100 and Oh ~ 0.04, while M∞ ranges from 0.3 to 1.2, which allows to study the influence of M∞exclusively. The main finding is that increasing M∞ disturbs the uniformity of the breakup fragment size and constrains the extent of the fragment distribution. Other intriguing observations include the appearance of liquid ligaments entrained in the droplet wake and the delay of the breakup at higher M∞.      «

This study experimentally investigates the effect of the freestream Mach number (M∞) on the droplet stripping breakup. Millimeter-sized ethylene glycol droplets are exposed to gas flows in a shock tube, and the breakup process is captured by an ultra-high-speed camera in combination with a Schlieren system. The flow conditions are maintained at We ~ 1100 and Oh ~ 0.04, while M∞ ranges from 0.3 to 1.2, which allows to study the influence of M∞exclusively. The main fi...     »