实测海浪方向谱的统计特征

Statistical Features of Measured Wave Directional Spectrum

本文根据仪器阵列测量和“９５６”测波浮标获得的个例方向谱资料，分析了不同波场类型的实测方向谱形状；计算了海浪能量相对于方向和频率的实际分布；结合实测的风要素，探讨了由台风边缘大风和寒潮大风引起的风浪峰频组成波方向与风向的对应关系。

Based on a vast amount of instrument array observational data and '956' wave buoy data, analysis of the shapes of the measured wave directional spectra in different kinds of wave fields and calculation of the relative distribution of the wave directional spectra energy were made using a form of accumulative addition of the wave energy ratio. The results show that not all the measured directional spectra from different kinds of wave fields are of the ideal single peak described in the present directional spectrum models, but some have two and even more peakes. When the wave patterns of the measured wave field comprise a single system of wind waves and swells, the directional spectrum is a single peak and its energy take a single peak symmetric distribution relative to the direction. The distribution of the energy is quite concentrated and more than 80×10 -2 of total energy is distributed within ±60° of the direction, which is similar to the case of S max =25 for the 'Guang Yi' directional function. The relative distribution of the swell directional spectrum energy is more concentrated as compared with the above case and more than 90×10 -2 of total energy is distrituted within ±40° of the direction, which is similar to the case of S max =75 for the 'Guang Yi' directional function. The directional spectrum of the mixed wave usually has two or more peakes. As the relative distribution of its energy is quite complex, it can not be described with the present directional spectrum model.