Related papers: Force and flow transition in plowed granular media
Monodisperse packings of dry, air-fluidized granular media typically exist between volume fractions from $\Phi$= 0.585 to 0.64. We demonstrate that the dynamics of granular drag are sensitive to volume fraction $\Phi$ and their exists a…
We studied the drag and lift forces acting on an inclined plate while it is dragged on the surface of a granular media, both in experiment and numerical simulation. In particular, we investigated the influence of the horizontal velocity of…
We investigate the drag forces acting on large objects moving through a granular packing immersed in water. In this aim, we conducted uplift experiments involving pulling out horizontal plates at a prescribed velocity vertically. During…
The mechanical response of a wet granular layer to imposed shear is studied experimentally at low applied normal stress. The granular material is immersed in water and the shear is applied by sliding a plate resting on the upper surface of…
We use confocal microscopy to study the motion of a magnetic bead in a dense colloidal suspension, near the colloidal glass transition volume fraction $\phi_g$. For dense liquid-like samples near $\phi_g$, below a threshold force the…
We report the experimental study of the bifurcations of a large-scale circulation that is formed over a turbulent flow generated by a spatially periodic forcing. After shortly describing how the flow becomes turbulent through a sequence of…
We investigate the conditions leading to large drag force fluctuations in granular materials. The study is based on a set of experimental drag tests, which involve pulling a plate vertically through a cohesionless granular material. In…
We introduce a simple model to describe the frictional properties of granular media under shear. We model the friction force in term of the horizontal velocity v and the vertical position z of the slider, interpreting z as a constitutive…
We discuss the behavior of partially wetting liquids on a rotating cylinder using a model that takes into account the effects of gravity, viscosity, rotation, surface tension and wettability. Such a system can be considered as a prototype…
We report on a particle-based numerical study of sheared amorphous solids in the dense slow flow regime. In this framework, deformation and flow are accompanied by critical fluctuation patterns associated with the macroscopic plastic…
We study fluctuations in the drag force experienced by an object moving through a granular medium. The successive formation and collapse of jammed states give a stick-slip nature to the fluctuations which are periodic at small depths but…
Using numerical simulations we examine the velocity fluctuations of a probe particle driven with constant force through a two-dimensional disordered assembly of disks which has a well-defined jamming point J at a density of \phi_J=0.843. As…
This paper investigates the flow past a flexible splitter plate attached to the rear of a fixed circular cylinder at a low Reynolds number of 150. A systematic exploration of the plate length ($L/D$), flexibility coefficient ($S^{*}$), and…
We investigate the force of flowing granular material on an obstacle. A sphere suspended in a discharging silo experiences both the weight of the overlaying layers and drag of the surrounding moving grains. In experiments with frictional…
We perform traction experiments on simple liquids highly confined between parallel plates. At small separation rates, we observe a simple response corresponding to a convergent Poiseuille flow. Dramatic changes in the force response occur…
We present experimental observations of the onset of flow (liquefaction) for horizontally vibrated granular materials. As the acceleration increases above certain value, the top layer of granular material liquefies, while the remainder of…
We study average flow properties in porous media using a two-dimensional network simulator. It models the dynamics of two-phase immiscible bulk flow where film flow can be neglected. The boundary conditions are biperiodic which provide a…
Fluctuations of the local volume fraction within granular materials have previously been observed to decrease as the system approaches jamming. We experimentally examine the role of boundary conditions and inter-particle friction $\mu$ on…
We numerically investigate the flow structure of periodic steady water waves of fixed relative mass flux propagating on rotational flows with piece-wise constant vorticity. We show that for wave solutions along the global bifurcation…
A net force can arise on objects which lie in systems with complex energy partitions, even if the system is on average stationary. These forces are usually called fluctuation forces, as they arise due to the objects modifying the character…