分别设计3种频率范围和8种方向间隔共24种谱空间离散方案,采用SWAN海浪模式对Winnie(1997)台风浪进行了数值模拟,并利用Topex/Poseidon卫星高度计观测的有效波高对各种方案的模拟结果进行对比分析,讨论了不同谱空间离散方案对台风浪模拟的影响。结果表明,频率范围相同的情况下,有效波高的模拟误差基本上随着方向间隔减小而减小,模拟结果对方向间隔分辨率比较敏感。方向间隔相同的情况下,SWAN模式默认频率范围(0.04~1.0Hz)模拟效果是所选择的3种频率范围中最差的,但不同频率范围模拟结果差别并不十分明显。方向间隔和频率范围存在相互匹配问题,当两者不匹配时会增大模拟误差。
In this paper, the third generation wave model ( Simulating Waves Nearshore, SWAN ) with a total of 24 discretization schemes in spectral space, three frequency ranges and eight directional resolutions are employed, and they are conducted to the typhoon-generated waves of Winnie (1997), respectively. The observed significant wave height retrieved from Topex/Poseidon altimeter and 24 individual simulation results are compared to evaluate the influence of discretization scheme on wave simulation. The results show that the simulation error is decreasing with the promotion of directional resolution for the given frequency range, which suggests that the simulation is sensitive to the directional resolution. Though the SWAN with default frequency range performs not so well for a given directional resolution, the simulation is not sensitive to the frequency range. Furthermore, it is important to the simulation for the matching between frequency range and directional resolution.