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Related papers: Grain size dependence of barchan dune dynamics

200 papers

As granular materials flow and settle, interactions among particles of different sizes or properties drive mixing and segregation, producing rich dynamics that reshape systems ranging from industrial hoppers to planetary surfaces. A…

Soft Condensed Matter · Physics 2026-04-28 Hugo N. Ulloa , Tomás Trewhela

We study the role of the unknown microphysical properties of carbonaceous dust particles in determining the amount and size distribution of carbonaceous dust condensed in type II supernova explosions. We parametrize the microphysical…

Solar and Stellar Astrophysics · Physics 2015-05-28 David W. Fallest , Takaya Nozawa , Ken'ichi Nomoto , Hideyuki Umeda , Keiichi Maeda , Takashi Kozasa , Davide Lazzati

We use a stochastic model and direct numerical simulation to study the impact of turbulence on cloud droplet growth by condensation. We show that the variance of the droplet size distribution increases in time as t^{1/2}, with growth rate…

Fluid Dynamics · Physics 2015-10-06 Gaetano Sardina , Francesco Picano , Luca Brandt , Rodrigo Caballero

Molecular dynamics studies of nono-sized rigid grains, droplets and bubbles in nano-sized pores indicate that the drag force may have a hydrodynamic form if the moving object is dense and small compared to the pore diameter. Otherwise, the…

Statistical Mechanics · Physics 2009-11-07 Nazar Sushko , Marek Cieplak

Nonequilibrium molecular dynamics simulations are used to study the shear thinning behavior of immiscible symmetric polymer blends. The phase separated polymers are subjected to a simple shear flow imposed by moving a wall parallel to the…

Soft Condensed Matter · Physics 2009-11-07 Sandra Barsky , Mark O. Robbins

Barchans are dunes commonly found in dune fields on Earth, Mars and other celestial bodies, where they can interact with each other. This article concerns experimental data for the flow over subaqueous barchans that are either isolated or…

Fluid Dynamics · Physics 2024-01-09 Jimmy Gabriel Alvarez , Danilo da Silva Borges , Erick de Moraes Franklin

Recent observations indicate that mm/cm-sized grains may exist in the embedded protostellar disks. How such large grains grow from the micron size (or less) in the earliest phase of star formation remains relatively unexplored. In this…

Earth and Planetary Astrophysics · Physics 2022-07-29 Yisheng Tu , Zhi-Yun Li , Ka Ho Lam

We introduce a new, discretized grain size evolution model, incorporated into the GIZMO code and coupled with FIRE-3 stellar feedback and ISM physics, to investigate variations in dust abundance, chemical composition, and grain sizes…

Astrophysics of Galaxies · Physics 2026-03-10 Caleb R. Choban , Samir Salim , Dušan Kereš , Julia Roman-Duval , Karin M. Sandstrom

Gravity-driven thick granular flows are relevant to many industrial and geophysical processes. In particular, it is important to know and understand the particle velocity distributions as we get deeper into the flow from the free surface.…

Soft Condensed Matter · Physics 2015-12-15 Etien Martinez , Oscar Sotolongo-Costa , Alfo Jose Batista-Leyva , Ernesto Altshuler

Grain growth fundamentally shapes the microstructure of crystalline materials upon annealing, affecting their overall mechanical and functional properties. Recently, it has been rationalized that grain growth in polycrystals does not result…

A layer of sand of thickness h flows down a rough surface if the inclination is larger than some threshold value theta which decreases with h. A tentative microscopic model for the dependence of theta with h is proposed for rigid frictional…

Materials Science · Physics 2014-11-19 Matthieu Wyart

We have studied the splashing dynamics of water drops impacting granular layers. Depending on the drop kinetic energy, various shapes are observed for the resulting craters. Experimental parameters that have been considered are : the size…

Fluid Dynamics · Physics 2010-10-18 G. Delon , D. Terwagne , N. Adami , A. Bronfort , N. Vandewalle , S. Dorbolo , H. Caps

We study the dynamics of large, charged dust grains in turbulent giant molecular clouds (GMCs). Massive dust grains behave as aerodynamic particles in primarily neutral dense gas, and thus are able to produce dramatic small-scale…

Astrophysics of Galaxies · Physics 2017-07-11 Hyunseok Lee , Philip F. Hopkins , Jonathan Squire

We study experimentally the collective motion of grains inside a U shaped tube undergoing vertical oscillations, and we develop a very simple quantitative model that captures relevant features of the observed behaviour. The height…

Soft Condensed Matter · Physics 2016-08-14 I. Sánchez , J. R. Darias , R. Paredes , C. J. Lobb , G. Gutiérrez

We have investigated the relationship between height and spacing of Barchan dunes which the coupled map lattice model numerically generates. There is a scaling relation between them and the values of the scaling exponents agree well with…

Pattern Formation and Solitons · Physics 2007-05-23 Jun Shibata , Y-h. Taguchi

Transverse dunes appear in regions of mainly unidirectional wind and high sand availability. A dune model is extended to two dimensional calculation of the shear stress. It is applied to simulate dynamics and morphology of transverse dunes…

Condensed Matter · Physics 2015-06-24 Veit Schwämmle , Hans J. Herrmann

Grains are determinant for setting the chemical, physical, dynamical, and radiative properties of all the media in which they are present. Their influence depends on the grain composition, size, and geometrical structure which vary…

Astrophysics of Galaxies · Physics 2018-10-03 N. Ysard , A. P. Jones , K. Demyk , T. Boutéraon , M. Koehler

Via event-driven molecular dynamics simulations we study kinetics of clustering in assemblies of inelastic particles in various space dimensions. We consider two models, viz., the ballistic aggregation model (BAM) and the freely cooling…

Statistical Mechanics · Physics 2018-04-04 Subhajit Paul , Subir K. Das

It is difficult to imagine a planet formation model that does not at some stage include a gravitationally unstable disc. Initially unstable gas-dust discs may form planets directly, but the high surface density required has motivated the…

Astrophysics · Physics 2009-11-13 Alexander Hubbard , Eric G. Blackman

We investigate the clustering and dynamics of nano-sized particles (nano-dust) in high-resolution ($1024^3$) simulations of compressible isothermal hydrodynamic turbulence. It is well-established that large grains will decouple from a…

Astrophysics of Galaxies · Physics 2020-01-08 Lars Mattsson , Johan. P. U. Fynbo , Beatriz. Villarroel