Breakup of single droplet induced by high weber number flow behind shock wave

Asahara, Makoto*; Iwasaki, Kodai*; Kamiya, Tomohiro ; Mizuno, Kyohei*; Iwatsuki, Kazuma*; Miyasaka, Takeshi*

Breakup of a single droplet induced by a high-velocity gas flow behind a shock wave was observed with high spatio-temporal accuracy imaging, and the behavior of fragment formation was observed. In the high Weber number region corresponding to catastrophic breakup, the wavelength of the upstream interfacial wave of the droplet was larger than the critical wavelength of the Kelvin-Helmholtz instability (wavelength in the stability region), which was roughly consistent with the theoretical wavelength of the Rayleigh-Taylor instability. Therefore, the upstream interfacial wave of the droplet is generated by the development of small disturbances due to the Rayleigh-Taylor instability. The measured fragment diffusion widths were found to be independent of the Weber number.