Filtration and separation of a mixture of different fluid components are fundamental in a wide variety of applications. These processes are used in the purification of water, for example, along with the development of chemical reactors for food processing and other biological applications. Intrinsic in these systems is the goal to remove contaminants or other fluid components from one fluid, or...

A bubble merged from two parent bubbles with different size tends to be placed closer to the larger parent. This phenomenon is known as the coalescence preference. Here we demonstrate that the coalescence preference can be blocked inside a densely packed cluster of bubbles. We utilized high-speed high-resolution X-ray microscopy to clearly visualize individual coalescence events inside densely ...

We present data on the pinch-off and coalescence of thin liquid alkane lenses floating on water. Pinch-off in quasi-2D lenses is distinctly different from pinch-off in axisymmetric 3D drops and involves a cascade of satellite droplets which extends to micron length scales. In contrast, coalescence of lenses is qualitatively similar to coalescence of 3D drops. Coalescence is predicted to involve...

Mechanisms and dynamics of bubble coalescence in silicic magmas 1 Jonathan M. Castro (University of Mainz) 2 Alain Burgisser (ISTO-CNRS) 3 Ian Schipper (ISTO-CNRS) 4 Simona Mancini (ISTO-Université d’Orléans) 5 6 Abstract 7 Bubble coalescence is an important process that strongly affects magmatic degassing. 8 Without coalescence, bubbles remain isolated from one another in the melt, severely 9 ...

By measuring or calculating coalescence times for several models of coalescence or evolution, with and without selection, we show that the ratios of these coalescence times become universal in the large size limit and we identify a few universality classes.

A common feature of many free surface flows—drop/bubble breakup or coalescence and film/sheet rupture—is the occurrence hydrodynamic singularities. Accurately computing such flows with continuum mechanical, multidimensional flow algorithms is a challenging task given these problems’ multiscale nature, which necessitates capturing dynamics occurring over disparate length scales across 5–6 orders...

The gradual transformation of a mushy zone during alloy solidification, from a continuous liquid film network to a fully coherent solid, has been simulated using a granular model. Based on a Voronoi tessellation of a random set of nucleation centers, solidification within each polyhedron is computed considering back-diffusion and coalescence. In the network of connected liquid films, a pressure...

We analyze axisymmetric near-contact motion of two drops under the action of an external force or imposed flow. It is shown that the far-field stress generated in the near-contact region by the outer flow qualitatively affects drainage of the thin fluid film separating the drops. If this stress acts radially outward, exponential film drainage occurs. For a radially inward far-field stress, film...

The Lees–Edwards description of bi-periodic boundary conditions has been extended to the streamfunction and streamfunction–vorticity formulation in sliding bi-periodic frames. The required compatibility conditions are formulated and uniqueness of the solution is shown. The model has been implemented in a spectral element method context to describe bulk shear behavior far away from walls, where ...

We introduce a new method to measure the lateral diffusivity of a surfactant monolayer at the fluid-fluid interface, called fluorescence recovery after merging (FRAM). FRAM adopts the same principles as the fluorescence recovery after photobleaching (FRAP) technique, especially for measuring fluorescence recovery after bleaching a specific area, but FRAM uses a drop coalescence instead of photo...