Deformation and relaxation of viscous thin films under bouncing drops

  title={Deformation and relaxation of viscous thin films under bouncing drops},
  author={Srinath Lakshman and Walter Tewes and Kirsten Harth and Jacco H. Snoeijer and Detlef Lohse},
  journal={Journal of Fluid Mechanics},
Abstract Thin, viscous liquid films subjected to impact events can deform. Here we investigate free-surface oil-film deformations that arise owing to the build up of air under the impacting and rebouncing of water drops. Using digital holographic microscopy, we measure the three-dimensional surface topography of the deformed film immediately after the drop rebound, with a resolution down to 20 nm. We first discuss how the film is initially deformed during impact, as a function of film thickness… 

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