孤立波作用下斜坡堤越浪量的数值模拟

海啸对海面上的船舶、建筑物及周围环境破坏极大,而对于海啸的研究通常采用孤立波来模拟.为了探究海啸对斜坡堤越浪的问题,在FLUENT软件中,建立二维数值波浪水槽,采用用户定义函数(user defined function,UDF)边界造波,流体体积函数(volume of fluid,VOF)方法追踪自由表面,模拟出孤立波波高随时间变化的情况.并利用斜坡堤数值波浪水槽模拟堤顶处的越浪量,与实验数据对比.进而,研究相对波高、相对超高、相对堤顶宽度对越浪量的影响.研究结果表明,孤立波在斜坡堤作用下,越浪量数值模拟的结果与实验值吻合较好;无量纲越浪量随着相对波高的增大而增大;随着相对超高、相对堤顶宽度的增大而减小;通过模拟不同堤顶宽度的越浪量,总结出孤立波越浪量沿堤顶宽度衰减的经验公式.

Numerical simulation on overtopping of solitary wave against a slope dike

Tsunamis can do great damages to ships, ocean and coastal buildings, and the solitary waves are usually used to simulate tsunami waves. In this work, the FLUENT software was used to establish a two-dimensional numerical wave flume with VOF method to track the the free surface, and interactions of the solitary waves and a slpope dike are carried out with a UDF boundary wave-making method. In the numerical wave flume, wave overpass at the top of dike was computed and compared with the experimental data. And the effects of relative wave height, relative height and relative width of levee roof on overtopping are also studied. The results show that the numerical simulation results of slope embankment under the action of solitary waves are in good agreement with the experimental values. Moreover, The dimensionless overtopping increases with the increase of relative wave height, and decreases with the increase of the width of relatively high and relative dike top. By simulating the overtopping of different widths of levee, an empirical formula of the wave-crossing of isolated wave along the width of levee was summarized.