Interaction of liquid droplets and liquid bubbles with planar shock waves

The interaction and breakup processes of 1.5 mm-diameter ethyl alcohol droplets and 5.1 mm-diameter water bubbles with planar shock waves were observed by using a double exposure holographic interferometer. Experiments were conducted on a 60 mm x 150 mm cross sectional shock tube for shock Mach number of 1.56 in air. Weber numbers of droplets and liquid bubbles were 5600 and 2800 respectively while their Reynolds numbers were 42,000 and 150,000. As a result, it is shown that the resulting holographic interferogram can eliminate the effect of the mists produced by the breakup of the droplet. It is demonstrated that the diameter of a breaking up droplet has been overestimated by up to 35 percent by comparing a holographic interferographic result with that of the image hologram from which the interferogram was reconstructed.