Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · cond-mat/0305357

Monodisperse Dry Granular Flows on Inclined Planes : Role of Roughness

C. Goujon·N. Thomas·B. Dalloz-Dubrujeaud
View original source ↗Read source document ↗Export metadata ↓

Abstract

Recent studies have pointed out the importance of the basal friction on the dynamics of granular flows. We present experimental results on the influence of the roughness of the inclined plane on the dynamics of a monodisperse dry granular flow. We found experimentally that it exists a maximum of the friction for a given relative roughness. This maximum is shown to be independent of the angle of the slope. This behavior is observed for four planes with different bump sizes (given by the size of the beads glued on the plane) from 200 microns to 2 mm. The relative roughness corresponding to the maximum of the friction can be predicted with a geometrical model of stability of one single bead on the plane. The main parameters are the size of the bumps and the size of the flowing beads. In order to obtain a higher precision, the model also takes into account of the spacing between the bumps of the rough plane. Experimental results and model are in good agreement for all the planes we studied. Other parameters, like the sphericity of the beads, or irregularities in the thickness of the layer of glued particles, are shown to be of influence on the friction.

Explore related subjects

cond-mat.softcond-mat.mtrl-sci

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

C. Goujon, N. Thomas, B. Dalloz-Dubrujeaud. 2003-05-15. Monodisperse Dry Granular Flows on Inclined Planes : Role of Roughness. https://doi.org/10.1140/epje%2Fi2003-10012-0

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Reciprocal theorem for ion-releasing colloidal particles

We describe a generalization of the reciprocal theorem for particles suspended in electrolyte solutions and subjected to an electric field that could be either applied or emerged spontaneously. Attention is focused on catalytic colloids that release ions. The power of the generalization is to capture the effect of formation of a secondary cloud around a catalytic particle, which is equivalent to accounting for an excess charge $Q$ of a system. Our results show that the propulsion speed of catalytic particles has an extra contribution proportional to $Q$ and an external field $E_{\infty}$. The derived equation for $Q$ reveals that its sign is defined by the difference in the ion diffusivity and the magnitude is controlled by the average flux of ions from the surface. We demonstrate the application of the generalized theorem to electro- and diffusiophoresis of homogeneously releasing ions passive particles, as well as to a self-propulsion of inhomogeneous active particles (microswimmers). It is shown that whilst in some situations the extra term in the reciprocal theorem vanishes or has a little effect on the particle mobility, in many others it may dramatically change its magnitude, and even sign. In addition, the relevance of our results for microswimmer interactions is discussed briefly.

cond-mat.soft↗
arXiv2026

Multigeometric Breathing Mode Framework for viruses

The estimation of the breathing mode frequency for viral capsids remains a persistent challenge across literature which spawned various frameworks and methodologies. However, discrepancies were observed between the experimental Low Frequency Raman Scattering (LFRS) and calculated pre-existing values. To solve this discrepancy, we propose a framework which is developed to determine the breathing-mode frequency by modelling the virus as a macroscopic coupled harmonic oscillator. By integrating mass-loading directly into the classical elastodynamic equations, this model yields an analytical expression that couples the system's total inertia with its specific geometry. Moreover, the viruses are segregated according to their geometries into three coordinates to acquire their respective geometric eigen values. Here we illustrate how the proposed Multigeometric Breathing mode Framework for Virus (MBFV) outperforms prior models by yielding closer values than the pre-existing frameworks upon validating against LFRS.

cond-mat.soft↗
arXiv2026

Insight into ordering at nematic twist-bend interfaces

Twist-bend nematics formed by achiral particles support heliconical domains of opposite handedness. Using Monte Carlo and molecular dynamics simulations of repulsive bent particles, we study the interface between two such domains. Rather than a gradually untwisting texture, we find a density-modulated splay-bend-twist structure. The density modulation is along the helix axis with a period of approximately half the bulk pitch, while the twist is locally enhanced in magnitude, alternates in sign, and vanishes only on an undulating surface. An explicit director interpolation shows how gradients along the helix axis and across the interface combine to produce an undulating zero-twist surface.

cond-mat.soft↗