Capillary bridges

A capillary bridge is a minimized surface of liquid or membrane created between two rigid bodies of arbitrary shape. Capillary bridges also may form between two liquids.[1] Plateau defined a sequence of capillary shapes[2] known as (1) nodoid with 'neck', (2) catenoid, (3) unduloid with 'neck', (4) cylinder, (5) unduloid with 'haunch' (6) sphere and (7) nodoid with 'haunch'. The presence of capillary bridge, depending on their shapes, can lead to attraction or repulsion between the solid bodies. The simplest cases of them are the axisymmetric ones. We distinguished three important classes of bridging, depending on connected bodies surface shapes:

  • two planar surfaces (fig.1)
fig.1 Concave capillary bridge between two planes(schematic representation)
  • planar surface and spherical particle (fig. 2)
fig.2 Concave capillary bridge between particles and flat surface(schematic representation)
  • two spherical particles (in general, particles may not be of equal sizes, fig. 3)
fig.3 Concave capillary bridge between two particles(schematic representation)

Capillary bridges and their properties may also be influenced by Earth gravity and by properties of the bridged surfaces. The bridging substance may be a liquid or a gas. The enclosing boundary is called the interface (capillary surface). The interface is characterized by a particular surface tension.

  1. ^ Ross, Sydney (1950). "The Inhibition of Foaming. II. A Mechanism for the Rupture of Liquid Films by Anti-foaming Agents". J. Phys. Chem. 54 (3): 429–436. doi:10.1021/j150477a018.
  2. ^ Kralchevsky, P.; Nagayama, K. (2001). Particles at Fluid Interfaces and Membranes. Amsterdam: Elsevier. pp. 469–502.