渤海和黄海北部波高与周期联合分析

JOINT ANALYSIS OF WAVE HEIGHT AND WAVE PERIOD IN THE BOHAI SEA AND NORTHERN YELLOW SEA

分析波高与周期的联合分布特征对于海洋平台设计、海洋工程建筑等有着重要的意义。基于SWAN模型模拟的波浪后报数据对渤海和黄海北部1999~2018年的波浪特征进行了统计分析。分别对20年的波高和周期数据进行了统计分析,得到了研究区域20年有效波高和波周期的季平均值和最大值的区域分布特征。然后以散布图的形式刻画了整个区域20年波高和周期的联合分布特征。为了更深入地研究波高和周期的联合分布规律,选择了两个研究点A1和A2,A1在渤海内部相对近岸, A2在黄海北部深海区。统计结果表明,在A1和A2,波高与周期的联合分布特征较为相似,均呈现斜三角形的分布特征,然而大波高大周期的波浪却呈现不同的分布特征。最后,利用20年的波浪后报数据,在A1和A2点构建了有效波高和谱峰周期的联合概率模型,并采用IFORM法得到了50年、100年和200年重现周期的环境等值线,为研究海域海上结构物的可靠性设计提供了参考。

The analysis of the joint distribution of wave height and wave period plays a significant role in the design of offshore platforms and marine constructions.A statistical investigation of wave characteristics during 1999~2018 in the Bohai Sea and northern Yellow Sea was conducted based on the hindcast data simulated by SWAN model.The 20-year wave height and wave period data were analyzed separately.The regional distributions of the 20-year seasonal mean and maximum of the wave height and wave period were obtained,and the joint distributions of the 20-year wave height and wave period over the whole region were characterized in the form of a scatter plot.To further understand the joint distribution of wave height and wave period,two sites(A1 and A2) were selected for the study.Site A1 was set in the interior of the Bohai Sea,and Site A2 in the deep-sea area of the northern Yellow Sea.Results show that the joint distribution of wave height and wave period at the two sites was similar in oblique triangle pattern.However,the wave with large wave height and large wave period presented different distribution characteristics at the two sites.Finally,the joint probability model of wave height and wave period was constructed for Sites A1 and A2 based on the 20-year hindcast data.The environmental contours of the 50-,100-,and 200-year return periods were obtained based on the IFORM method,which provides a reference for the reliability design of the offshore structures in the future.