Related papers: Impact-induced energy transfer and dissipation in …
In nature, granular materials fail in abrupt avalanches, earthquakes, and other hazardous events, and also creep over time. Proposed failure mechanisms for these systems are broadly framed as friction-limited. However, mechanical…
This paper, in French, describes a series of completely different behaviours of the mechanics of granular matter, which are obtained experimentally using periodic forcing at different amplitude, frequency and orientation. It starts with the…
Non-cohesive granular media exhibit complex responses to sudden impact that often differ from those of ordinary solids and liquids. We investigate how this response is mediated by the presence of interstitial gas between the grains. Using…
In this paper we briefly review a model that describes the diffusion-controlled aggregation exhibited by particles as they are deposited on a surface. This model allows to understand many experiments of thin film deposition. In the first…
We study the stability, the clustering and the phase-diagram of free cooling granular gases. The systems consist of mono-disperse particles with additional non-contact (long-range) interactions, and are simulated here by the event-driven…
The paper addresses the underlying source of two forms of induced anisotropy in granular materials: contact orientation anisotropy and contact force anisotropy. A rational, mathematical structure is reviewed for the manner in which fabric…
We argue that impact velocities between dust grains with sizes less than $\sim 0.1$ $\mu m$ in molecular cloud cores are dominated by drift arising from ambipolar diffusion. This effect is due to the size dependence of the dust coupling to…
We study the effect of pre-collisional velocity correlations on granular shear flow by molecular dynamics simulations of the inelastic hard sphere system. Comparison of the simulations with the kinetic theory reveals that the theory…
We report an experimental study of a dilute "gas" of inelastically colliding particles excited by vibrations in low gravity. We show that recording the collision frequency together with the impulses on a wall of the container gives access…
Radio, X-ray, and gamma-ray observations provide us with strong evidence of particle acceleration to multi-TeV energies in various astrophysical sources. Diffusive shock acceleration is one of the most successful models explaining the…
In this letter we investigate the dynamics of magnetic energy growth in small-scale dynamo by studying energy transfers, mainly energy fluxes and shell-to-shell energy transfers. We perform dynamo simulations for magnetic Prandtl number…
It is a common point that "soft" condensed matter (like granular materials or foams) can reduce damage caused by impact or explosion. It is attributed to their ability to absorb significant energy. This is certainly the case for a…
The problem of simulating the interaction of spacecraft travelling at velocities necessary for starflight with the interplanetary and interstellar medium is considered. Interaction of protons, atoms, and ions at kinetic energies relative to…
We describe a setup to perform systematic studies on the spreading of droplets of complex fluids under microgravity conditions. Tweaking the gravitational acceleration under which droplets are deposited provides access to different regimes…
We have developed a kinetic theory of hard needles undergoing binary collisions with loss of energy due to normal and tangential restitution. In addition, we have simulated many particle systems of granular hard needles. The theory, based…
The heating of inertial confinement fusion (ICF) target by fast electrons, which are generated as a result of laser interaction with expanding plasma (corona) of a target, is investigated theoretically. It is shown that due to remoteness of…
Pour sand into a container and only the grains near the top surface move. The collective motion associated with the translational and rotational energy of the grains in a thin flowing layer is quickly dissipated as friction through…
Dense granular flows are well described by several continuum models, however, their internal dynamics remain elusive. This study explores the contact force distributions in simulated steady and homogenous shear flows. Results demonstrate…
Binary collisions of the gyrating charged particles in an external magnetic field are considered within a classical second-order perturbation theory, i.e., up to contributions which are quadratic in the binary interaction, starting from the…
In this thesis are presented analytical results and numerical simulations concerning resonant processes in a frozen gas. This work was begun with the intent of modeling experiments involving energy transfer due to dipole-dipole interactions…