深海岛礁水动力及三维计算模型研究

The construction and ecological environment protection of the reef islands are increasing in recent years, the corresponding study of the coastal hydrodynamics in the reef environment is thus required. The unique characteristics of the reef bathymetry result in an extremely complex coastal hydrodynamics, deep understanding of them is even beyond the ability of the traditional research results and approaches that widely utilized in the field of the coastal engineering. The present study aims to investigate the coastal hydrodynamics via a combination of physical experiments and numerical simulation. A three-dimensional non-hydrostatic wave model will be developed after a systematic study on its theoretical property and computational method. The physical experiments will be conducted in the wave flume in the State Key Laboratory of Coastal and Offshore Engineering. The big roughness of the reef bathymetry is assumed as porous medium and thus its effect on the wave motion is taken into account. Via the combination of numerical simulation and physical experiments, we mainly investigate the spatial distribution, motion characteristics and generation mechanism of the coastal hydrodynamics, as well as the influences of the reef bathymetry on the coastal hydrodynamics. The above study is expected to provide a solid understanding and efficient computational tool of coastal hydrodynamics in the reef environment, thus favoring the construction and ecological environment protection of the reef islands.

当前深海岛礁工程和生态环境保护的步伐日益加快，亟需开展岛礁水动力的研究以提供理论和技术支持。岛礁地貌的特殊性导致岛礁水动力异常复杂，传统的用于海岸工程的研究方法和研究结果不能妥善解决深海岛礁水动力问题。本项目通过数值计算与物理模型实验相结合的方法研究深海岛礁水动力运动特征和产生机理。计算模型建立方面，在系统的理论分析和计算方法研究基础上，建立适用于岛礁水动力计算的三维非静压波浪模型。物理模型实验方面，利用海岸和近海工程国家重点实验室先进的设备仪器和技术，开展大粗糙度岛礁海床上波浪传播实验。将大粗糙度海床处理为大孔隙多孔介质。通过物理模型实验和数值计算，研究深海岛礁主要水动力现象的空间分布、运动特征和产生机理，明确岛礁地形特征尺度参数和海床粗糙度对水动力的影响机制，为岛礁工程建设和生态环境保护提供理论支持和计算方法储备。

岛礁地貌的特殊性导致岛礁海域的近岸水动力特征与传统海岸迥异，现有的研究方法和研究结果不能妥善解决深海岛礁水动力问题。本项目通过数值计算与物理模型实验相结合的方法研究深海岛礁水动力运动特征和产生机理。理论和数值模型方面，通过系统研究提出了新型多层Boussinesq水波理论、建立了数值模型并进行了广泛的验证，建立了三维非静压波浪传播数值模型；开展了极端波浪在典型岛礁海床剖面上传播演化的物理模型试验。通过数值模拟和物理模型实验研究了波浪在典型岛礁海床剖面上传播演化的相关水动力特性。