The Cook's instability : coiling of a thread of honey

Abstract

We combine analytical, numerical, and experimental approaches to study the dynamics of the ``liquid rope coiling" that occurs when a thin stream of viscous fluid like honey falls onto a surface. As the fall height increases, coiling traverses a sequence of four dynamical regimes (viscous, gravitational, inertio-gravitational, and inertial) characterized by different balances of the forces acting on the rope. The inertio-gravitational regime is particularly rich, exhibiting multiple states that correspond to resonant modes of the rope's ``tail''.