Based on fifty one groups of data on direction distribution measured from buoy sites, several important spectrum parameters including distribution characteristics of the measured data’s spectrum, the Wen’s direction spectrum and the Donelan function are analyzed from the perspectives of standard deviation of directional distribution function and statistical results. Then, a numeric calculation model based on the Monte Carlo method is proposed in this work. At the same time—based on Weierstrass self-affine fractal function—numeric simulation of random sea surface is conducted by modifying the bilateral power law. The analysis of the numeric calculation results under different wind directions, speeds and fetches proves that both methods can be adopted for different water directional distributions and target spectrum models. In addition, this study compares the characteristic wave within different distribution frequency domains in the main wave direction and in its orthogonal direction. It is proved that the fractal method cannot fully reflect the anisotropy of gravity wave and tension wave in the superposition direction, however, it can maintain the similarity of overall energy part with the rough length of the waves. Moreover, there are still limitations of the fractal method in the numeric modeling of undeveloped sea surface.

中文翻译：

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基于分形法和蒙特卡罗法的​​二维随机海面数值计算比较研究

以51组浮标测得的方向分布数据为基础，从方向分布函数的标准差和统计角度分析了测得的光谱分布特征、温氏方向谱和Donelan函数等几个重要的光谱参数。结果。然后，本文提出了一种基于蒙特卡罗方法的数值计算模型。同时，基于Weierstrass自仿射分形函数，通过修正双边幂律对随机海面进行数值模拟。对不同风向、风速和取力下的数值计算结果的分析证明，两种方法都可以用于不同的水向分布和目标谱模型。此外，本研究比较了主波方向及其正交方向不同分布频域内的特征波。证明分形方法不能完全反映叠加方向上重力波和拉力波的各向异性，但可以保持整体能量部分与波的粗略长度的相似性。此外，分形方法在未开发海面数值模拟中还存在局限性。它可以保持整体能量部分与波浪的粗略长度的相似性。此外，分形方法在未开发海面数值模拟中还存在局限性。它可以保持整体能量部分与波浪的粗略长度的相似性。此外，分形方法在未开发海面数值模拟中还存在局限性。