Small blast waves initiated by laser-induced breakdowns were visualized by schlieren imaging; two methods were applied to determine the initial blast wave energies from the expansion trajectories. Both methods proved very useful, providing very simular and reasonable results over a wide range of breakdown energies. The blast waves consume a significant percentage of the breakdown energies, which even inreases with decreasing energy: At a breakdown energy of 246 mJ approximately 51 % was transferred into the blast wave. At an energy of 12mJ it increased to 77 %. The breakup of ethanol and Jet A-1 droplet chains (d ≈ 100 μm) caused by the blast waves and their post-shock flow fields was visualized with the shadowgraph method. Droplets were broken up into several secondary droplets at close distances of 5 to 7 mm from the origin of the blast waves. With increasing distance the breakup weakened and was finally replaced by droplet oscillation at 9 mm distance. Contrary to Jet A-1 droplets, ethanol droplets reliably broke up at 8mm distance. This was attributed to the surface tension of Jet A-1, which is approximately 5 to 15 % greater compared to ethanol. Hence, Jet A-1 proved slightly more resistant to blast wave-induced breakup than ethanol.
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