Multiple coexisting states of a falling viscous thread
Habibi, Mehdi; Rahmani, Yasser; Bonn, Daniel; Ribe, Neil M.
This fluid dynamics video shows experiments in which a thin thread of viscous fluid (viscosity 950 cS) ejected at a rate 0.19 ml/s from a hole 2 mm in diameter falls a distance 14 cm onto a solid plate. The thread exhibits three different states that succeed each other in time in a random manner: (1) axisymmetric stagnation flow; (2) steady coiling; and (3) rotatory folding. Transitions among these states are caused by spontaneous finite-amplitude perturbations that travel down the thread.
APS DFD 2009 Gallery of Fluid Motion
free-surface flows; liquid rope coiling