English
Related papers

Related papers: Minimal model for aeolian sand dunes

200 papers

We propose a minimal model for aeolian sand dunes. It combines an analytical description of the turbulent wind velocity field above the dune with a continuum saltation model that allows for saturation transients in the sand flux. The model…

Soft Condensed Matter · Physics 2009-11-07 Klaus Kroy , Gerd Sauermann , Hans J. Herrmann

We derive a phenomenological continuum saltation model for aeolian sand transport that can serve as an efficient tool for geomorphological applications. The coupled differential equations for the average density and velocity of sand in the…

Materials Science · Physics 2009-11-07 G. Sauermann , K. Kroy , H. J. Herrmann

Wind-blown sand, or "saltation", ejects dust aerosols into the atmosphere, creates sand dunes, and erodes geological features. We present a comprehensive numerical model of steady-state saltation that, in contrast to most previous studies,…

Fluid Dynamics · Physics 2009-01-05 Jasper F. Kok , Nilton O. Renno

Starting from the physics on the grain scale, we develop a simple continuum description of aeolian sand transport. Beyond popular mean-field models, but without sacrificing their computational efficiency, it accounts for both dominant grain…

Soft Condensed Matter · Physics 2012-09-27 Marc Lämmel , Daniel Rings , Klaus Kroy

We present an analytical model of aeolian sand transport. The model quantifies the momentum transfer from the wind to the transported sand by providing expressions for the thickness of the saltation layer and the apparent surface roughness.…

Soft Condensed Matter · Physics 2019-09-20 Thomas Pähtz , Jasper F. Kok , Hans J. Herrmann

Barchans are crescent-shaped sand dunes forming in aride regions with unidirectional wind and limited sand supply. We report analytical and numerical results for dune shapes under different environmental conditions as obtained from the…

Soft Condensed Matter · Physics 2009-11-11 Klaus Kroy , Sebastian Fischer , Benedikt Obermayer

It is now an accepted fact that the size at which dunes form from a flat sand bed as well as their `minimal size' scales on the flux saturation length. This length is by definition the relaxation length of the slowest mode toward…

Soft Condensed Matter · Physics 2009-11-13 B. Andreotti , P. Claudin

Wind-driven sand transport generates atmospheric dust, forms dunes, and sculpts landscapes. However, it remains unclear how the sand flux scales with wind speed, largely because models do not agree on how particle speed changes with wind…

Geophysics · Physics 2017-03-10 Raleigh L. Martin , Jasper F. Kok

The mesoscale structure of aeolian sand transport determines a variety of natural phenomena studied in planetary and Earth science. We analyze it theoretically beyond the mean-field level, based on the grain-scale transport kinetics and…

Soft Condensed Matter · Physics 2017-12-06 Marc Lämmel , Klaus Kroy

We model formation and evolution of transverse dune fields. In the model, only the cross section of the dune is simulated. The only physical variable of relevance is the dune height, from which the dune width and velocity are determined, as…

Statistical Mechanics · Physics 2007-05-23 J. H. Lee , A. O. Sousa , E. J. R. Parteli , H. J. Herrmann

Desert surfaces are typically non uniform, with individual sand dunes generally surrounded by gravel or non-erodible beds. Similarly, beaches vary in composition and moisture that enhances cohesion between the grains. These bed…

Our aim in this note is to introduce and study a mathematical model for the description of traveling sand dunes. We use surface flow process of sand under the effect of wind and gravity. We model this phenomena by a non linear…

Analysis of PDEs · Mathematics 2021-03-23 Noureddine Igbida , Fahd Karami , Driss Meskine

A simple model for the dynamics of dunes associated with vegetation is proposed. Using the model, formation processes of transverse dunes, parabolic dunes and elongated parabolic dunes according to two environmental factors: i)the amount of…

Pattern Formation and Solitons · Physics 2015-06-26 Hiraku Nishimori , Hirohisa Tanaka

The dune morphodynamics study is under highly focused recently, due to aeolian process induced nonlinear correlation to sediment modification over bedform. Surface stress, inflicted by aloft upcoming wind, impacts, crucially, the sediment…

Fluid Dynamics · Physics 2020-04-13 Chao Wang

The saturation length of aeolian sand transport ($L_s$), characterizing the distance needed by wind-blown sand to adapt to changes in the wind shear, is essential for accurate modeling of the morphodynamics of Earth's sandy landscapes and…

Atmospheric and Oceanic Physics · Physics 2015-08-19 Thomas Pähtz , Amir Omeradžić , Marcus V. Carneiro , Nuno A. M. Araújo , Hans J. Herrmann

The wavelength at which a dune pattern emerges from a flat sand bed is controlled by the sediment transport saturation length, which is the length needed for the sand flux to adapt to a change of wind strength. The influence of the wind…

Soft Condensed Matter · Physics 2008-06-25 B. Andreotti , P. Claudin , O. Pouliquen

We present in this paper a simplification of the dune model proposed by Sauermann et al. which keeps the basic mechanisms but allows analytical and parametric studies. Two kinds of purely propagative two dimensional solutions are exhibited:…

Condensed Matter · Physics 2015-06-24 Bruno Andreotti , Philippe Claudin

We present a continuous model capable of demonstrating some salient features of aeolian sand ripples: the realistic asymmetric ripple shape, coarsening of ripple field at the nonlinear stage of ripple growth, saturation of ripple growth for…

Soft Condensed Matter · Physics 2009-11-13 Edgar Manukyan , Leonid Prigozhin

Natural wind-eroded soils contain a mixture of particle sizes. However, models for aeolian saltation are typically derived for sediment bed surfaces containing only a single particle size. To nonetheless treat natural mixed beds, models for…

Geophysics · Physics 2019-04-23 Raleigh L. Martin , Jasper F. Kok

In zones of loose sand, wind-blown sand dunes emerge due the linear instability of a flat sedimentary bed. This instability has been studied in experiments and numerical models but rarely in the field, due to the large time and length…

‹ Prev 1 2 3 10 Next ›