近岸港口风暴潮与台风浪相互作用的数值模拟

为了模拟近岸港口风暴潮与台风浪的相互作用,利用ECOMSED和SWAN,采用嵌套方法,使用海图水深数据、Holland台风模型气压场,选择具有代表性的200808号台风为天气背景,规划4组数值试验,通过单向耦合研究该港区及邻近海域的台风浪和风暴潮水位相互影响。使用ECOMSED模式,按是否考虑波浪作用分别计算苏澳港风暴潮水位。对比结果表明,考虑海浪影响的风应力以后,风暴潮水位更加接近实测值,海浪通过风应力对苏澳港风暴潮位有全局性的调制作用,苏澳港内聚集更多的海水,内外的水位高度差加大,海平面更加倾斜。使用SWAN模式,按是否考虑风暴潮位影响分别计算了苏澳港的台风浪,试验结果表明,波高受风暴潮位的影响是局部的,靠近岸边的有效波高有所增大,增大的幅度约1m,而水位较深的地方有效波高变化不明显。

Numerical simulation of interaction of stormsurge and typhoon wave on near shore harbor

To estimate the interactive process of the storm surge and typhoon wave of the Suao Harbor in Taiwan Island by using the ECOMSED and SWAN models, the Typhoon Fungwong illustrated by the Holland typhoon model was selected as the meteorological background, the chart data were adopted and the four level nested grids were set ECOMSED is started two times to run for the water level with/without wave effects. The results show that the wave affects the whole Suao Harbor's water level field through the wind shear stress. The water levels with effects of wave are closer to the measurements than those without effects of wave. The typhoon wave makes more water accumulate into Suao Harbor, and consequently, water level difference of the harbor between the inside and outside increases and the slope of the sea surface is intensified. SWAN is also started two times to run for the typhoon wave with and without water level effects. The results show that the effects of water level on the typhoon wave of the Suao Harbor is prominent on the area with shallow water but invisible in the deep water. The increase of the significant wave height on the north cape can reach up to about 1 m.