Eur. Phys. J. E (2005) 16: 401-407
https://doi.org/10.1140/epje/i2004-10090-4

Symmetry-breaking transitions and dissociation of two-dimensional Plateau borders

¹ Departamento de Engenharia de Materiais and Instituto de Ciência e Engenharia de Materiais e Superfıcies, Instituto Superior Técnico, Avenida Rovisco Pais, P-1049-001, Lisbon, Portugal
² Faculdade de Engenharia, Universidade Católica Portuguesa, Estrada de Talaıde, P-2635-631, Rio de Mouro, Portugal

^* e-mail: piteixeira@fe.ucp.pt

Received: 19 November 2004
Accepted: 18 January 2005
Published online: 3 March 2005

Abstract

We have experimentally studied the dissociation/coalescence of internal Plateau borders (PBs) in simple monolayer bubble clusters, as a result of changing the liquid fraction. At large liquid content, the clusters consist of n bubbles of the same size, symmetrically placed around an internal n-sided PB (n-PB). On decreasing the liquid fraction we observed symmetry-breaking transitions in the 4- and 5-bubble clusters (but not in the 3-bubble cluster), followed by dissociation of the PBs. We used the Surface Evolver to determine the various equilibrium configurations of the corresponding two-dimensional wet clusters and their surface energies. The sequence of 4-bubble cluster configurations observed on varying the liquid fraction correlates qualitatively with that predicted on the basis of Surface Evolver calculations. The same is not true of the 5-bubble cluster.