Barchan dunes in two dimensions: experimental tests for minimal models.
Barchan dunes in two dimensions: experimental tests for minimal models.
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DOI：
10.1103/physreve.78.021304
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发表时间：
2008-08
期刊：
影响因子：
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通讯作者：
C. Groh;A. Wierschem;N. Aksel;I. Rehberg;C. Kruelle
中科院分区：
文献类型：
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作者：
C. Groh;A. Wierschem;N. Aksel;I. Rehberg;C. Kruelle
通过实验研究了剪切流作用下的二维单一沙丘。从最初准备的三角形堆，可以观察到以恒定的质量、形状和速度快速松弛到稳态解。这个吸引器展示了自然界中发现的所有barchan沙丘的特征，即缓缓倾斜的迎风侧、峰顶、边缘和陡峭的背风面。达到稳态的驰豫时间随质量的增加而增加。对于小沙丘，我们发现与固定的高度-长度长宽比有很大的偏差。根据最近的理论模型预测，迁移速度与沙丘的长度成反比。
A well-defined two-dimensional single barchan dune under the force of a shearing water flow is investigated experimentally. From an initially prepared triangular heap a rapid relaxation to a steady-state solution is observed with constant mass, shape, and velocity. This attractor exhibits all characteristic features of barchan dunes found in nature, namely a gently inclined windward side, crest, brink, and steep lee face. The relaxation time towards the steady state increases with mass. For small dunes we find significant deviations from a fixed height-length aspect ratio. As predicted by recent theoretical models, the migration velocity scales reciprocal to the length of the dune.