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arXiv · 2604.26407

Impulse-driven capillary detachment

Dilip Kr. Maity·Sandip Dighe·Nilamani Sahoo·Tadd Truscott
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Abstract

Capillary interfaces subjected to impulsive forcing arise in many natural and technological systems, yet the pathway by which rapid substrate motion is converted into droplet detachment remains unclear. Here we study this process in a controlled setting: a liquid droplet resting on a taut wire that is plucked and suddenly released. The resulting transverse wave imparts a brief inertial forcing at the droplet base, initiating rapid stretching that precedes sheet formation and jet breakup. We show that the maximum extension prior to detachment is set by the mechanical work transmitted from the wire through capillary traction at the three-phase contact line, balanced by viscous dissipation during filament extension. This energetic balance identifies the contact line as the pathway by which mechanical impulse is converted into capillary deformation and governs impulsive droplet detachment.

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Dilip Kr. Maity, Sandip Dighe, Nilamani Sahoo, Tadd Truscott. 2026-04-29. Impulse-driven capillary detachment. https://arxiv.org/abs/2604.26407

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