On the diffusivity in coastline dynamics
On the diffusivity in coastline dynamics
复制标题
海岸线动力学的扩散率
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
A. Falqués
中科院分区：
文献类型：
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作者：
A. Falqués
重新讨论了海岸线动力学的一维扩散方程。发现扩散系数的经典估计将其预测为从1.25到无穷大的因子，因为扩散系数可能变为零，而经典预测总是正值。过度预测取决于波陡度和波入射角。涌浪比海浪大，并且随着角度的增加而增加。对于中等角度，它可以很容易地约为10倍。负扩散率发生在大角度的情况下，与大角度形态动力学不稳定性一致。
The 1D diffusion equation for the dynamics of the coastline is revisited. It is found that the classical evaluation of the diffusivity coefficient over‐predicts it by a factor ranging from 1.25 up to infinity since the diffusivity may become zero while the classical prediction is always positive. The over‐prediction depends on wave steepness and wave incidence angle. It is larger for swell than for sea waves and it increases with increasing angle. For moderate angles it can easily be about a factor 10. Negative diffusivity occurs in case of large angles, consistent with the large angle morphodynamic instability.