波流混合作用的完全非线性数值水槽模型  

A fully nonlinear numerical flume model for wave-current interactions

作　　者：宁德志[1,2] 陈丽芬[1] 田宏光[1] 

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]南京水利科学研究院水资源与水利工程科学国家重点实验室,江苏南京210029

出　　处：《哈尔滨工程大学学报》2010年第11期1450-1455,共6页Journal of Harbin Engineering University

基　　金：国家自然科学基金资助项目(50709005和50921001);国家科技重大专项基金资助项目(2008ZX05026-02);水资源与水利工程科学国家重点实验室开放基金资助项目(2009491611);中央高校基本科研业务费专项基金资助项目(DUT10JN03)

摘　　要：针对海洋环境的波流混合作用问题,本文利用时域高阶边界元方法建立模拟波流混合作用的完全非线性数值水槽模型,其中自由水面满足完全非线性自由水面条件.采用混合欧拉-拉格朗日方法追踪流体瞬时水面,运用四阶Runga-Kutta方法更新下一时间步的波面和速度势.为了避免由于网格运动变形而引起数值不稳定问题,在每一时间步内对网格进行重新划分,通过采用二次形状函数计算新网格的物理量和几何量.与原Boussinesq模型结果对比吻合很好,验证了本模型的准确性.进一步研究了水流作用下波面的变化及水流对波浪非线性的影响,逆流使波浪非线性进一步增强,而顺流使波浪非线性减弱.Concerning the problem of wave-current interactions in an ocean environment, a fully nonlinear numerical flume model simulating wave-current interactions was developed based on the time-domain higher-order boundary element method. The fully nonlinear free water surface boundaries were satisfied. The mixed Eulerian-Lagrangian scheme was adopted to track the transient free surface with the fourth-order Runga-Kutta method for refreshing wave profile and velocity potential at the next time step. The meshes were divided again at each time step to avoid numerical instabilities caused by mesh motions. The physical and geometrical variables at the new positions were computed by using the quadratical shape function in the remeshing processes. The present numerical model was verified by comparison with published Boussinesq model results. The variations of wave profile under water flow action and the influence caused by water flow to wave nonlinearity were further studied. The findings show that wave nonlinearity is amplified and weakened by counter and fair currents, respectively.

关 键 词：数值波浪水槽 时域高阶边界元 完全非线性 波流作用 混合欧拉-拉格朗日方法 

分 类 号：O242.1[理学—计算数学]