High-speed ethanol micro-droplet impact on a solid surface

Recently, droplet impact draws great attention in the fluid mechanics. In previous work, micro-droplet impact on a solid surface at velocities up to 100 m s$^{\mathrm{-1}}$ was studied. However the study was only on water micro-droplets. In this study, we experimentally investigate high-speed impact of ethanol micro-droplets in order to confirm the feature about maximum spreading radius with another liquid. A droplet is generated from a laser-induced high-speed liquid jet. The diameter of droplets is around 80 $\mu $m and the velocity is larger than 30 m s$^{\mathrm{-1}}$. The surface tension of ethanol is 22.4 mNm$^{\mathrm{-1}}$ and density is 789 kgm$^{\mathrm{-3}}$. Weber number ranges We \textgreater 1000. By using a high-speed camera, we investigate the deformation of droplets as a function of Weber number.