不同波峰定义对波峰统计特征值的影响

Effect of Different Wave Crest Definitions on Wave Crest Statistics

在三维随机海浪数值模拟的基础上,获得了波峰的空间分布。为了验证由不同的波峰定义方法得到的波峰长度和波峰方向角等特征量的准确性,对直接利用波峰边界上距离最远的两点之间距离定义波峰长度和利用椭圆拟合波峰和以椭圆的要素定义波峰长度2种不同方法得到的波峰长度统计结果进行了比较,发现由2种方法定义得到的波峰特征量的值基本一致,尤其是波峰长度个数的统计值极为接近,由2种方法得到的统计值精确度相当。这表明,不同定义方法对边界不规则波峰长度统计值的影响较小。

In this paper, the spatial distributions of wave crest are obtained on the basis of the numerical simulationn of 3-D random waves, and the crest distributions are used to examine the correctness of the crest characteristic values (including the crest length and direction angle) obtained by two crest defining methods. One method is to define the longest distance between two points at the crest boundary as the crest length, and the other is to fit an ellipse to the crest area and take the major axis of ellipse as the crest length. It is shown from the comparison between the crest length statistics obtained by the two methods that the two kinds of crest characteristic values are basically consistent with each other, especially the statistics of crest length are quite close to each other, and the accuracies of their statistics are about the same, which indicates that the effect of two crest defining methods on the crest length statistics is small.