Related papers: Nonlinear Force Propagation during Granular Impact
The non-Newtonian character of granular flow in a vertical pipe is analyzed. The time evolution of the flow velocity and the velocity fluctuations (or granular temperature) is derived. The steady state velocity has a power law dependence on…
We present several numerical results on granular mixtures. In particular, we examine the efficiency of diffusion as a mixing mechanism in these systems. The collisions are inelastic and to compensate the energy loss, we thermalize the…
The gravity-driven discharge of granular material through an aperture is a fundamental problem in granular physics and is classically described by empirical laws with different fitting parameters. In this Letter, we disentangle the mass…
The bulk behaviour of granular materials is tied to its mesoscale and particle-scale features: strength properties arise from the buildup of various anisotropic structures at the particle-scale induced by grain connectivity (fabric), force…
Impact dynamics during collisions of spheres with granular media reveal a pronounced and non-trivial dependence on volume fraction \phi. Post impact crater morphology identifies the critical packing state \phi_{cps}, where sheared grains…
Oblique, low-velocity impacts onto extraterrestrial terrain are an inevitable occurrence during space exploration. We conduct two-dimensional discrete simulations to model such impacts into a bed of triangular grains. Finite element method…
The intermittent compact flow of glass beads in a vertical glass pipe of small diameter is studied experimentally by combining particle fraction, pressure, and air and grain flow rates measurements with a spatio-temporal analysis of the…
In a recent paper (Gonzalez et al., 2023), we investigated the motion of grains within a granular bed sheared by a viscous fluid, and showed how segregation and hardening occur in the fluid- (bedload) and solid-like (creep) regions. In this…
We use simulations to investigate collision time distributions as one approaches the static limit of steady-state flow of dry granular matter. The collision times fall in a power-law distribution with an exponent dictated by whether the…
The strength of granular materials is highly dependent on grain connectivity (fabric), force transmission, and frictional mobilization at the particle scale. Furthermore, these bulk properties are strongly dependent on the geometry and…
We present an experimental study of velocity statistics for a partial layer of inelastic colliding beads driven by a vertically oscillating boundary. Over a wide range of parameters (accelerations 3-8 times the gravitational acceleration),…
We study the dynamics of an athermal inertial run-and-tumble particle moving in a shear-thickening medium in $d=1$. The viscosity of the medium is represented by a nonlinear function $f(v)\sim\tan(v)$, while a symmetric dichotomous noise of…
Semi-empirical molecular dynamics is used to simulate hydrocarbon grain sputtering and collisions which are extremely difficult to study experimentally. This microscopic and dynamic approach is particularly suited to high velocity impacts,…
We report two-dimensional simulations of strongly vibrated granular materials without gravity. The coefficient of restitution depends on the impact velocity between particles by taking into account both the viscoelastic and plastic…
We study the fragment size distributions after crushing of single and many particles under uniaxial compression inside a cylindrical container by means of numerical simulations. Under the assumption that breaking goes through the bulk of…
The quasistationary spreading of a circular liquid drop on a solid substrate typically obeys the so-called Tanner law, with the instantaneous base radius R(t) growing with time as R ~ t^{1/10} -- an effect of the dominant role of capillary…
We study the propagation of tension caused by an external force along a long polymeric molecule in two different settings, namely along a free polymer in 3d space being pulled from one end, and along a pre-stretched circular polymer,…
In this paper, we perform molecular dynamics (MD) simulations to study the random packing of spheres with different particle size distributions. In particular, we deal with non-Gaussian distributions by means of the L\'evy distributions.…
The velocity distribution of a fluidized dilute granular gas in the direction perpendicular to the gravitational field is investigated by means of Molecular Dynamics simulations. The results indicate that the velocity distribution can be…
Under an externally applied load, granular packings form force chains that depend on the contact network and moduli of the grains. In this work, we investigate packings of variable modulus (VM) particles, where we can direct force chains by…