Coexistence of Two Singularities in Dewetting Flows: Regularizing the Corner Tip

Ivo Peters (1, 2) , Jacco Snoeijer (2) , Adrian Daerr (1) , Laurent Limat (1)

1 MSC - Matière et Systèmes Complexes
2 University of Twente

Entrainment in wetting and dewetting flows often occurs through the formation of a corner with a very sharp tip. This corner singularity comes on top of the divergence of viscous stress near the contact line, which is only regularized at molecular scales. We investigate the fine structure of corners appearing at the rear of sliding drops. Experiments reveal a sudden decrease of tip radius, down to 20 microns, before entrainment occurs. We propose a lubrication model for this phenomenon, which compares well to experiments. Despite the disparity of length scales, it turns out that the tip size is set by the classical viscous singularity, for which we deduce a nanometric length from our macroscopic measurements.

Domaines: Formation de Structures et Solitons [nlin.PS]; Matière Molle [cond-mat.soft]; Biomécanique [physics.med-ph]; Mécanique des fluides [physics.class-ph]; Milieux fluides et réactifs

Ivo Peters, Jacco Snoeijer, Adrian Daerr, Laurent Limat. Coexistence of Two Singularities in Dewetting Flows: Regularizing the Corner Tip. Physical Review Letters, 2009, 103 (11), pp.114501. ⟨10.1103/PhysRevLett.103.114501⟩. ⟨hal-02377545⟩