Impact Behavior of Single Water Drop Impacting onto Burning Ethanol Surface

A series of experimental and theoretical works are performed to enrich the previous research concerning single water drop impacting on burning ethanol surface. Three typical impact regimes including crater-first-jet, crater-second-jet, and surface bubble are discussed in detail, and an impact regime map is built up. For crater-first-jet and crater-second-jet regimes, the dimensionless maximum crater depth increases with the impact Weber number, but there is a sharp decrease for the regime transitioning from crater second-jet to surface bubble. In addition, the theoretical maximum crater depth and jet length scales are derived based on energy conservation and conversion. For crater formation, as the drop initial total energy increases, gravity gradually dominates the surface tension effects. For jet formation, however, the surface energy is around nine-times larger than gravitational potential energy when the energy stored in crater is the lowest.