Related papers: Plug regime in water fluidized beds in very narrow…
We present experimental results on slow flow properties of a granular assembly confined in a vertical column and driven upwards at a constant velocity V. For monodisperse assemblies this study evidences at low velocities ($1<V<100 \mu m/s$)…
Pebble-bed nuclear reactor technology, which is currently being revived around the world, raises fundamental questions about dense granular flow in silos. A typical reactor core is composed of graphite fuel pebbles, which drain very slowly…
We present both experimental and numerical investigations of compaction in granular materials composed of rods. As a function of the aspect ratio of the particles, we have observed large variations of the asymptotic packing volume fraction…
In this fluid dynamics video, we report on experiments of large aspect ratio capillary surfaces supported by a helical wire. These open channels are potentially useful for fluid management at low Bond numbers. The experiments were performed…
Fluidic transport in inverted T-shaped cavities with the flow entering through the top and exiting from the two bottom outlets experiences an interesting phenomenon that causes particles having density lower than that of the fluid medium to…
We analyze the flow of a liquid foam between two plates separated by a gap of the order of the bubble size (2D foam). We concentrate on the salient features of the flow that are induced by the presence, in an otherwise monodisperse foam, of…
Taylor bubbles are a feature of the slug flow regime in gas-liquid flows in vertical pipes. Their dynamics exhibits a number of transitions such as symmetry-breaking in the bubble shape and wake when rising in downward-flowing and stagnant…
An improved understanding of how vortices develop and propagate under pulsatile flow can shed important light on the mixing and transport processes including the transition to turbulent regime occurring in such systems. For example, the…
The flow near a moving contact line depends on the dynamic contact angle, viscosity ratio, and capillary number. We report experiments involving immersing a plate into a liquid bath, concurrently measuring the interface shape, interfacial…
Turbulent stripe, which would occur in turbulent channel flows at transitional Reynolds numbers, was studied experimentally by flow visualization using reflective flake particles. In a range of bulk mean Reynolds number Re = 1700-2000, the…
Recent experiments of thin films flowing down a vertical fiber with varying nozzle diameters present a wealth of new dynamics that illustrate the need for more advanced theory. We present a detailed analysis using a full lubrication model…
We characterize the different morphologies adopted by a drop of liquid placed on two randomly oriented fibers, which is a first step toward understanding the wetting of fibrous networks. The present work reviews previous modeling for…
We propose a model to describe the quasistatic shearing of dry granular materials, which notably captures the differences in velocity profiles recently observed in 2 and 3-D Couette flow experiments. In our scheme, the steady-state flow is…
We simulate the granulation process of solid spherical particles in the presence of a viscous liquid in a horizontal rotating drum by using molecular dynamics simulations in three dimensions. The numerical approach accounts for the cohesive…
Aerobreakup of fluid droplets under the influence of impulsively generated high-speed gas flow using an open-ended shock tube is studied using experiments and numerical simulations. Breakup of mm-sized droplets at high Weber number was…
This experimental study focuses on the characteristics of air-water two-phase interfacial structure. Interfacial parameters including void fraction, interfacial area concentration, and bubble interfacial velocity are measured using…
A numerical hydrodynamic model of a vibrated granular bed in 2D is elaborated based on a highly accurate Shock Capturing scheme applied to the compressible Navier-Stokes equations for granular flow. The hydrodynamic simulation of granular…
A gravity-driven flow of grains through a narrow pipe in vacuum is studied by means of a one-dimensional model with two coefficients of restitution. Numerical simulations show clearly how density waves form when a strikingly simple…
The kinematic flow pattern in slow deformation of a model dense granular medium is studied at high resolution using \emph{in situ} imaging, coupled with particle tracking. The deformation configuration is indentation by a flat punch under…
Granular materials do not flow homogeneously like fluids when submitted to external stress,but often form rigid regions that are separated by narrow shear bands where the material yields and flows. This shear localization impacts their…