Shape evolution of numerically obtained subaqueous barchan dunes

On the crescentic shape of barchan dunes

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 latter are crescentic and emerge under a unidirectional wind, with a low sand supply. Here, a 3d model for barchan based on existing 2d model is proposed. After ...

On the shape of barchan dunes

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 so-called ‘minimal model’ of aeolian sand dunes. The profiles of longitudinal vertical slices (i.e. along the wind direction) are analyzed as a function of wind ...

The shape of the barchan dunes of Southern Morocco

We present detailed shape measurements of several barchan dunes in southern Morocco, near Laayoune. Using these ˆ data, we disprove the concept of shape invariance of barchan dunes of different sizes. Nevertheless, some parts of the barchan dune scale and we try to distinguish these from non-scaling ones. Furthermore, we point out the importance of the exact position of the brink for the overal...

The Shape of the Barchan Dunes in the Arkhangelsky

Sand dunes are beautiful sand patterns formed by the wind, and have been seen in many places on Mars. In particular barchan dunes, which have a crescent shape, propagate on solid ground under unidirectional winds and are very common on earth’s deserts and coasts, have been observed forming corridors on the floor of martian craters and also on the north pole. However, barchan dunes on Mars have ...

Subaqueous Barchan dunes in turbulent shear flow. Part 2: Fluid flow