| 摘要: |
| Johns变边界模型用于海湾海域风暴潮漫滩计算时，由于岸界弯曲较大，而影响了计算的稳定性和精度，本文针对这个问题，导出了极坐标下的连续移动边界模型，从而改善了对岸界弯曲较大海域的风暴潮漫滩计算。通过对1969年黄河口沿岸一带水域风暴潮漫滩的模拟，证明这种极坐标变边界模型用于海湾海域的风暴潮湿滩计算，优于Johns变边界模型。 |
| 关键词: 浅海动力学 风暴潮 漫滩 变边界模型 极坐标方程 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目，49070255号 |
|
| THE ADVANCEMENT AND APPLICATION OF A VARIABLE BOUNDARY MODEL IN A POLAR COORDINATE TRANSFORMATION |
|
Shi Fengyan, Sun Wenxin
|
|
Institute of Physical Oceanography, Ocean University of Qingdao, Qingdao 266003
|
| Abstract: |
| Johns advanced a variable boundary model using coordinate transformation in calculating storm surge flooding. The model is mainly characterized by proper employment of the kinematic boundary conditions and continuous movement of the land boundary. This sort of variable boundary model, however, may cause numerical unstability due to over-curving of the land boundary. So, it is necessary to limit the calculated area with the curve land and to reduce the time step too. To solve this problem, the authors used a variable boundary model with polar coordinates. Adjusting the coordinate origin point to fit the curve of the polar coordinates and the land boundary as much as possible enlarges the calculated area. Numerical experiments proved the high numerical stability in the calculation within the curved land boundary area. This model was used to simulate the storm surge flooding in the Huanghe Delta on 23 April 1969. The simulation result shows that the polar coordinate model obviously improves the calculation accuracy in the area of the Taoerhe River where Johns’ model performed unsatisfactorily, and the relative error of the predicted inundation area is 2.5% less than that of Johns’. |
| Key words: Shallow sea dynamics, Storm surge, Inundation, Variable boundary model, Polar coordinate equation |
