渤海湾风浪预报数值模式的研究

A study of the numerical forecast model of wind waves in Bohai Bay

为提高渤海海域海浪数值预报工作的精度,从风浪模式的角度,借助SWAN模型的物理过程,针对风输入项中线性系数的改进进行了论证。与荣城站观测结果对比表明,默认线性系数0.001 5较为合理。结合Komen、Janssen和Westhuysen 3种不同风指数增长表达式和对应的白浪破碎表达式,设计和研究不同组合方案下,风浪模式在渤海湾海数值模拟中的适用性。3个方案模拟的波浪特征值与实测值进行比较,结果显示,有效波高值与实测值变化趋势相同,模拟平均周期均偏小,且Westhuysen方案模拟效果最好。在计算结果统计分析中,模拟结果与实测值的相关系数相差不大,模拟效果较理想。

In order to enhance the accuracy of the numerical prediction of waves in Bohai Bay, the improvement of linear coefficients for the wind input is demonstrated with the aid of the physical processes of the SWAN model, from the perspective of wave patterns. It has been shown that 0.001 5 is a more reasonable default of the linear coefficient in contrast to the observations of the Rongcheng buoy. Combined with the three wind exponential expressions of Komen, Janssen and Westhuysen and the corresponding whitecapping dissipation expressions, the applicability of the wave mode for the numerical simulation of waves in Bohai Bay was designed and researched with different portfolio schemes. Consequently, the characteristic values and measured values of the three schemes were compared and the results showed that the effective wave height has the same change trend with the measured ones. Both of them have a smaller average cycle during the simulation. Furthermore, Westhuysen has been found to be the best one among the three schemes. With the statistical analysis of the calculation results, it has been found that there is little difference between the correlation coefficients with the simulated and measured values, so the simulation results are satisfactory .