Spooling and disordered packing of elastic rods in cylindrical cavities
1 Laboratoire de Physique Statistique, Ecole Normale Supérieure, UPMC Paris 6, Université Paris Diderot, CNRS 24 rue Lhomond, 75005 Paris, France
2 ENSTA ParisTech, Unité de Mécanique - Chemin de l'Hunière, 91761 Palaiseau, France
Received: 2 August 2013
Accepted: 10 October 2013
The compaction of elastic rods in rigid cylindrical cavities is experimentally performed. The results show two main packing behaviours: an ordered regime in which the rod spools on the internal surface of the cavity and a disordered phase where the orientation of the coils is randomly distributed. The phase diagram separating these two packing configurations is determined as a function of the aspect ratio of the container and of the intrinsic curvature of the rod. A theoretical stability analysis and an experimental study of the dynamics of the rod at the injection point allow to describe different instability mechanisms that drive the transitions from ordered to disordered packing, leading to the identification of the different disordering scenarios.
PACS: 46.32.+x – Static buckling and instability / 46.70.Hg – Membranes, rods, and strings / 61.43.-j – Disordered solids
© EPLA, 2013