广东阳西近岸海域海浪谱分析

Wave spectrum analysis of Guangdong Yangxi offshore area

根据广东阳西近岸海域测站1a实测共4 949组的原始随机波面观测记录,用自相关函数法和快速傅里叶变换法进行谱估计,得到波谱各特征参数,并与实测波面统计的特征值进行比较,经分析,选用快速傅里叶变换法估计研究海域的实测谱,对粗谱进行平滑和分析,筛选出研究海域海浪的样本谱498个,将平滑后的谱形无维量化,得到广东阳西海域海浪无维量平均谱曲线并求出对应谱参数,计算得到谱峰频率f0为0.121,特征频率μ10、μ20分别为1.929、2.733,谱宽度ε、ν为0.83、1.39.采用5种理论频谱模式对实测无维量谱进行拟合,根据拟合结果推荐γ=1.920 5的JONSWAP谱或者b=5.7、δ=6.0、k=0.5的莆田谱作为广东阳西近岸海域的海浪谱型,对该海区的工程建设、海浪预报警报和海浪理论研究具有较好的参考作用,对我国其他类似海域也有一定的参考价值.

Adopting the autocorrelation function and the fast Fourier transform method,this study estimated the Guangdong Yangxi offshore wave spectrum on the basis of a total of 4 949 sets of original random wave surface observation records,and compared it with the measured surface wave statistical eigenvalue.After analysis,the fast Fourier transform was employed to study the measured wave spectrum of the study area.By smoothing and analyzing the raw wave spectrum,498 sample spectrums of the study area were selected.We got the normalized average spectrum line of Guangdong Yangxi offshore area by normalizing the smoothed spectrum,and calculated the corresponding spectrum parameters.The peak frequency f0 was 0.121.The characteristic frequency μ10 and μ10were 1.929 and 2.733.The spectrum width ε and ν were 0.83 and 1.39.The measured spectrum was fitted with five kinds of theoretical frequency spectrum model.According to the fitting results,we recommend JONSWAP（γ=1.920 5） or Putian（b=5.7、δ=6.0、k=0.5） as the representation wave spectrum male of Guangdong Yangxi offshore area,This study provides a good reference for the construction,wave warning and forecast,and wave theoretical research of the studied area.It also has certain reference value for the similar sea area in China.