相关论文: A Model of Barchan Dunes Including Lateral Shear S…

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…

Barchans are isolated mobile dunes often organized in large dune fields. Dune fields seem to present a characteristic dune size and spacing, which suggests a cooperative behavior based on dune interaction. In Duran et al. (2009), we propose…

Aeolian sand dunes originate from wind flow and sand bed interactions. According to wind properties and sand availability, they can adopt different shapes, ranging from huge motion-less star dunes to small and mobile barchan dunes. The…

Barchans are crescentic dunes propagating on a solid ground. They form dune fields in the shape of elongated corridors in which the size and spacing between dunes are rather well selected. We show that even very realistic models for…

Almost fifty years of investigations of barchan dunes morphology and dynamics is reviewed, with emphasis on the physical understanding of these objects. The characteristics measured on the field (shape, size, velocity) and the physical…

Barchan dunes emerge as a collective phenomena involving the generation of thousands of them in so called barchan dune fields. By measuring the size and position of dunes in Moroccan barchan dune fields, we find that these dunes tend to…

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…

Barchan dunes, or simply barchans, are crescent-shaped dunes found in diverse environments such as the bottom of rivers, Earth's deserts and the surface of Mars. In a recent paper [Phys. Rev. E 101, 012905 (2020)], we investigated the…

Barchans are dunes of high mobility which have a crescent shape and propagate under conditions of unidirectional wind. However, sand dunes only appear above a critical size, which scales with the saturation distance of the sand flux [P.…

Barchan dunes were found to transform into parabolic dunes and vice versa when the amount of vegetation on and around them changes. This work presents the first numerical simulation of this effect. We propose a continuum model for the…

Barchans are eolian dunes of crescent shape found on Earth, Mars and other celestial bodies. Among the different types of barchan-barchan interaction, there is one, known as chasing, in which the dunes remain close but without touching each…

Beautiful dune patterns can be found in deserts and along coasts due to the instability of a plain sheet of sand under the action of the wind. Barchan dunes are highly mobile aeolian dunes found in areas of low sand availability and…

In nature, barchan dunes typically exist as members of larger fields that display striking, enigmatic structures that cannot be readily explained by examining the dynamics at the scale of single dunes, or by appealing to patterns in…

Barchan dunes --- crescent-shaped dunes that form in areas of unidirectional winds and low sand availability --- commonly display an asymmetric shape, with one limb extended downwind. Several factors have been identified as potential causes…

We demonstrate the feasibility of studying dunes in a laboratory experiment. It is shown that an initial sand pile, under a wind flow carrying sand, flattens and gets a shape recalling barchan dunes. An evolution law is proposed for the…

Barchans are dunes of crescentic shape found on Earth, Mars and other celestial bodies, growing usually on polydisperse granular beds. In this Letter, we investigate experimentally the growth of subaqueous barchans consisting of bidisperse…

Sand dunes are ubiquitous in nature, and are found in abundance on Earth and other planetary environments. One of the most common types are crescent-shaped dunes known as barchans, whose mid-line could be assumed to behave as 2D dunes. In…

The collision processes of two crescentic dunes called barchans are systematically studied using a simple computer simulation model. The simulated processes, coalescence, ejection and reorganization, qualitatively correspond to those…

The dune skeleton model is a reduced model to describe the formation process and dynamics of characteristic types of dunes emerging under unidirectional steady wind. Using this model, we study the dependency of the morphodynamics of…

Crescent shaped barchan dunes are highly mobile dunes that are usually presented as a prototypical model of sand dunes. Although they have been theoretically shown to be unstable when considered separately, it is well known that they form…