东海海啸反问题预报模式研究——以日本“3·11”海啸为例

采用COMCOT数值模式,将日本东海岸划分为18个单位震源,建立了日本东海岸海啸数据库并用非负约束的最小二乘法建立反问题预报模式。将本模式应用于日本"3·11"海啸,计算所得的海啸初始水位有10 m的抬高与3 m的降低,与前人研究结果基本一致,预报的浮标水位与实测资料符合良好。对比浙江省近岸潮位站实测海啸波高,预报值与实测值偏差较大。若采用反问题反演的震源,通过COMCOT非线性模式求解近岸水位,可以大幅提高预报精度。     

孤立波爬坡的二维数值模拟

波浪在滩地上以及遇海岸工程后传播发生变形、爬坡等现象,对其进行数值模拟具有广阔的工程应用背景.应用基于Boltzmann方程的KFVS(kinetic flux vector splitting)格式求解二维浅水方程,同时采用干底Riemann解模拟动边界问题.模型模拟了孤立波在滩地上传播变形、爬坡的过程,以及孤立波在滩地上遇圆柱后绕射、变形和爬坡的过程.计算结果与实验结果非常吻合,表明模型具有较大的推广应用价值.     

REFINED RISK ASSESSMENT OF STORM SURGE DISASTER IN COASTAL PLAIN: A CASE STUDY OF PINGYANG COUNTY

As the risk of storm surge on coastal plains increases, the research on disaster risk assessment is fundamental for disaster management. Disaster risk assessment tends to develop towards the direction of refinement and it gradually plays a more important role. As regards the characteristics of storm tide disaster in coastal plain, the paper uses refined floodplain numerical model which combines typhoon, flood, astronomical tide and waves. The model also considers influencing factors of dike-breaking, micro-topography and buildings. Precise calculation is executed for the range and the submerged depth caused by floodplain flow in coastal plain. Based on 3S technology, disaster-bearing bodies are subdivided into the smallest unit of the ground object, and the vulnerability of these units is evaluated. Refined risk assessment of storm surge disaster for the coastal plain is obtained, and the detailed distribution of risk areas at different risk levels is achieved. These results can be widely applied in many fields, such as disaster prevention and mitigation, urban planning, industrial arrangement, disaster insurance and so on.     

钱塘江河口杭州湾风暴潮溢流计算方法研究

建立钱塘江河口杭州湾风暴潮模型,探讨风暴潮出现溢流的计算方法。将可能出现溢流的沿海堤防以及海水侵入的陆地均依照高程概化为计算区域,采用糙率控制潮水的溢流流量,以模型的堤顶单宽流量和根据计算潮位采用宽顶堰公式换算流量的一致性来率定糙率值。在此基础上模拟了风暴潮漫溢堤防的过程,结果表明风暴潮出现溢流后,钱塘江河口杭州湾之间两岸大片的陆地存在淹没风险,沿程潮位由于溢流出现不同程度的降低响应。     

非粘性沙坝溃决数学模型及求解

考虑一维陡坡浅水方程与Exner方程耦合构建漫顶溃坝数学模型,利用Roe格式黎曼近似解法求解,并用预测-校正法处理源项保证水流、泥沙侵蚀输运和底床演变过程的计算稳定.模型实例计算结果表明,该方法能较好地计算非粘性模型沙坝漫顶溃决问题,可为溃坝数值计算提供新的思路.     

江苏沿海台风暴潮过程中的波浪增水分布研究

基于浅水方程和第三代波浪模型,构建了江苏沿海的风暴潮和台风浪耦合模型,并通过对天文潮、风暴潮和台风浪的模拟对模型进行验证.通过比较6场典型台风过程中江苏沿海的波浪增水特征,剖析了江苏沿海波浪增水的量级及空间分布特征.研究表明:受岸滩地形控制,不同台风暴潮期间江苏沿海最大波浪增水分布呈现类似特征,总体上,江苏中部和南部沿...