Resumen
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.