Drop fragmentation due to hole formation during Leidenfrost impact

Anne-Laure Biance (1) , Christophe Pirat (2) , Christophe Ybert (1)

1 LPMCN - Laboratoire de Physique de la Matière Condensée et Nanostructures
2 INLN - Institut Non Linéaire de Nice Sophia-Antipolis

Drop impacts on a smooth plate heated above the Leidenfrost temperature are investigated in the range of large Weber number. Liquid fragmentation due to the rupture of the expanding lamella during the impact—by hole nucleation and subsequent growth—is studied. Control of this rupturing process is achieved experimentally through the use of single model-defects attached to the substrate which act as an initiating spots for the hole formation, whereas the liquid does not contact the substrate. Overall, the lamella rupture is shown to take place above a critical impact velocity, the value of which decreases with increasing defect size. Comparing this rupture mechanism to classical splash, it is shown to be the relevant fragmentation phenomenon below a critical ratio between drop R0 and defect d sizes of R0 / d < 40.

Domaines: Dynamique des Fluides [physics.flu-dyn]

Anne-Laure Biance, Christophe Pirat, Christophe Ybert. Drop fragmentation due to hole formation during Leidenfrost impact. Physics of Fluids, 2011, 23 (2), ⟨10.1063/1.3553277⟩. ⟨hal-01628774⟩