The Rayleigh capillary instability of a cylindrical interface between two immiscible fluids is one of the most fundamental in fluid dynamics. As Plateau observed from energetic considerations and Rayleigh clarified through hydrodynamics, such an interface is linearly unstable to fission due to surface tension. In traditional descriptions of this instability it occurs everywhere along the cylind...

the serpentinization of the harzburgitic mantle section of the bou azzer neoproterozoic ophiolite is studied by field mapping, structural observations, optical micrography, sem and x-ray diffractometry, and relationships with co, ni, cr and sulphides minerals are discussed. serpentinization occurred in two major steps with, i) intra-oceanic pseudomorphic serpentinization materialized by the iso...

The understanding of the spreading of liquids on solid surfaces is an important challenge for contemporary physics. Today, the motion of the contact line formed at the intersection of two immiscible fluids and a solid is still subject to dispute. In this paper, a new picture of the dynamics of wetting is offered through an example of non-Newtonian slow liquid movements. The kinematics of liquid...

We introduce a new class of Green-Naghdi type models for the propagation of internal waves between two (1 + 1)-dimensional layers of homogeneous, immiscible, ideal, incompressible, irrotational fluids, vertically delimited by a flat bottom and a rigid lid. These models are tailored to improve the frequency dispersion of the original bi-layer Green-Naghdi model, and in particular to manage high-...

The Saffman-Taylor problem addresses the morphological instability of an interface separating two immiscible, viscous fluids when they move in a narrow gap between two flat parallel plates (Hele-Shaw cell). In this work, we extend the classic Saffman-Taylor situation, by considering the flow between two curved, closely spaced, concentric spheres (spherical Hele-Shaw cell). We derive the mode-co...

This review discusses the rheology of interfaces that separate two, immiscible fluids. Unlike interfaces at the fluid/solid boundary, these surfaces are mobile and deform. In the presence of amphiphiles that collect at these interfaces, they can become highly structured and non-Newtonian. These nonlinear responses to flow have profound implications on many physical processes and examples can be...

A weakly nonlinear model is proposed for the Rayleigh-Taylor instability in the presence of surface tension. The dynamics of a multimode perturbation of the interface between two incompressible, inviscid, irrotational, and immiscible fluids is analyzed. The quadratic and cubic nonlinear effects are taken into account. They include the nonlinear corrections to the exponential growths of the fund...

Bioremediation processes are negatively affected by the low aqueous solubility of some contaminants; therefore their bioavailability may be enhanced by the addition of surfactants. These compounds are organic molecules that can be chemically and biologically produced. Surfactants contain both hydrophilic and hydrophobic groups, therefore reducing surface and interfacial tensions of immiscible f...

The understanding of the spreading of liquids on solid surfaces is an important challenge for contemporary physics. Today, the motion of the contact line formed at the intersection of two immiscible fluids and a solid is still subject to dispute. In this paper, a new picture of the dynamics of wetting is offered through an example of non-Newtonian slow liquid movements. The kinematics of liquid...

A phase-field method is applied to the modeling of flow and breakup of droplets in a T-shaped junction in the hydrodynamic regime where capillary and viscous stresses dominate over inertial forces, which is characteristic of microfluidic devices. The transport equations are solved numerically in the three-dimensional geometry, and the dependence of the droplet breakup on the flow rates, surface...