2020/01/24 by Pallav Kant, Robin B. J. Koldeweij, Kirsten Harth +2
Engineering · Materials Science · Physics and Astronomy · #Classical mechanics #Fluid Dynamics Simulations and Interactions #Fluid Dynamics and Heat Transfer #Kinetics #Materials science #Mechanics #Physics #Surface Modification and Superhydrophobicity #cond-mat.soft #physics.app-ph #physics.flu-dyn
paper · pdf · doi:10.1073/pnas.1912406117
openalex publication_date 2020/01/24 · arxiv created 2020/02/03 · arxiv updated 2020/02/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Freezing or solidification of impacting droplets is omnipresent in nature and technology, be it a rain droplet falling on a supercooled surface; in inkjet printing, where often molten wax is used; in additive manufacturing or metal-production processes; or in extreme ultraviolet lithography (EUV) for the chip production, where molten tin is used to generate the EUV radiation. For many of these industrial applications, a detailed understanding of the solidification process is essential. Here, by adopting an optical technique in the context of freezing-namely, total-internal reflection (TIR)-we elucidate the freezing kinetics during the solidification of a droplet while it impacts on an undercooled surface. We show that at sufficiently high undercooling, a peculiar freezing morphology exists that involves sequential advection of frozen fronts from the center of the droplet to its boundaries. This phenomenon is examined by combining elements of classical nucleation theory to the large-scale hydrodynamics on the droplet scale, bringing together two subfields which traditionally have been quite separated. Furthermore, we report a self-peeling phenomenon of a frozen splat that is driven by the existence of a transient crystalline state during solidification.