Dynamics Of Liquid Bridges Research Articles

Cylindrical liquid bridges squeezed between parallel plates: Exact Stokes flow solutions and hydrodynamic forces

The problem of a dynamic liquid bridge between moving parallel plates is introduced. For the case of the Stokes flow in a cylindrical bridge driven by a slow change of the distance between the plates, an exact infinite-series solution is constructed, without invoking the lubrication approximation which was never surmounted in previous theories of dynamic liquid bridges. The boundary conditions at the free surface are fully satisfied, and the singularities of physical quantities at the moving contact line are avoided by allowing a minute but nonzero slip velocity. It is shown that, for narrower bridges, the ‘‘nonlubricative’’ contribution to hydrodynamic forces may become comparable with the force associated with the lubrication approximation.

The influence of the outer bath in the dynamics of axisymmetric liquid bridges

The main effects on the dynamics of a liquid bridge due to the presence of an outer liquid, as occur in experiments using the Plateau-tank technique, are considered. The one-dimensional nonlinear model developed here allows us to perform the computation of both breaking processes and oscillatory motions of slender liquid bridges, although in this paper only the results concerning breaking processes are reported. Additionally, the oscillatory motions are studied both experimentally and by using a new linear model. Results from both sources show good agreement.

One-dimensional self-similar solution of the dynamics of axisymmetric slender liquid bridges

Liquid bridges appear in a large variety of industrial processes such as the so-called floating-zone technique, used in recent years in crystal growth and in purification of high-melting-point materials.In this paper the dynamics of axisymmetric, slender, viscous liquid bridges having volume close to the cylindrical one, and subjected to a small gravitational field parallel to the axis of the liquid bridge, is considered within the context of one-dimensional theories. Although the dynamics of liquid bridges has been treated through a numerical analysis in the inviscid case, numerical methods become inappropriate to study configurations close to the static stability limit because the evolution time, and thence the computing time, increases excessively. To avoid this difficulty, the problem of the evolution of these liquid bridges has been attacked through a nonlinear analysis based on the singular perturbation method and, whenever possible, the results obtained are compared with the numerical ones.