寒潮影响下江苏沿海风浪场数值模拟研究

Research on the numerical simulation of wind wave field affected by a cold wave in Jiangsu coast

基于第三代浅水波浪数值预报模型SWAN,建立自西北太平洋嵌套至东中国海、江苏沿海的三重嵌套模型,对2010年12月12日至15日江苏沿海寒潮大风引起的风浪过程进行了数值模拟研究。利用西北太平洋和江苏沿海实测数据对模型进行了验证,结果表明SWAN嵌套模型能较好地模拟江苏沿海寒潮风浪场的时空分布。通过响水站实测数据对江苏沿海底摩擦系数进行了率定,研究表明选取Collins拖曳理论中摩擦因数C_f=0.001时,有效波高模拟误差相对较小。寒潮风浪场的特征分析表明,有效波高分布与风场分布基本一致,寒潮风浪在江苏沿海北部影响较为显著,辐射沙洲附近由于其特殊地形影响相对较小。

Based on the third-generation wave model SWAN, establishing a triple nested mode from the Northwest Pacific to the East China Sea, then to Jiangsu coast, conducting a numerical simulation of wind wave field under the influence of a cold wave during 12 to 15 December 2010 in Jiangsu coast. By comparing the Northwest Pacific and Jiangsu coastal observed data with the SWAN simulation results, it indicates that SWAN nested model can well reproduce temporal and spatial distribution of the wind wave field affected by cold waves in Jiangsu coast. Meanwhile with the Xiangshui observed data, the bottom friction coefficient was calibrated in Jiangsu coastal, our analyses show that Collins coefficient of 0. 001 can reduce the frictional dissipation effect. The wind and wave field characteristic analysis indicates that the distribution of significant wave height is basically the same with the wind distribution. The wave effect is significant in the northern coast, whereas due to the special terrain it has little effect in the radial sand ridges area.