港珠澳大桥西人工岛桥结合段波浪演变数值模拟

Numerical simulation of waves elevation at the west island⁃bridge joint of Hong Kong⁃Zhuhai⁃Macao Bridge

近年来海洋极端天气频发,港珠澳大桥西人工岛地处外海,与其相连接的桥梁非通航跨的桥面高程较低,容易受到海浪侵袭,威胁到岛桥功能的正常发挥和结构自身安全。针对西人工岛桥结合部周围的复杂地形条件,采用OpenFOAM®开源程序,分别对S、SSW和SW三个方向的极端波浪进行了数值模拟。通过数值计算结果与物理模型试验测量值的比较验证了的模型的准确性。分析了不同方向入射波的波高和沿岛体斜坡爬高的变化规律。随着波浪入射角的增大,人工岛南侧斜坡的波浪爬高呈逐渐减小,但在岛体西端靠近桥梁的位置处,波浪爬高逐渐增大;同时也反映了越浪和桥面上水风险的大小。研究旨在为实际工程的管理和设计提供参考。

In recent years,marine extreme weather occurrs frequently.The west island of the Hong Kong⁃Zhuhai⁃Macao Bridge is located in the open sea,and the bridge deck of the non⁃navigable span connected to the island is relatively low in elevation.Therefore,it is exceptionally vulnerable to huge waves,threatening the island and bridge􀆳s normal function and structural safety.Considering the complete topographic conditions around the west island and bridge joint,numerical simulations of waves elevation with incident directions of S,SSW,and SW were carried out by OpenFOAM®,a free code for CFD.The numerical model was verified by comparing the results obtained from the computation and the physical model test.The variation rules of wave heights and wave get⁃up under waves with different incident directions were analyzed.The results show that the wave get⁃up on the south slope of the west island is gradually reduced with the increase of angles of incident waves,whereas it is increased on the island􀆳s west side near the bridge,which also reflects the risk of wave overtopping and the bridge􀆳s green water.The study aims at providing a reference for the management and design of practical engineering.