考虑粘性效应的波-流和海洋结构物相互作用的全非线性模拟研究

项目名称： 考虑粘性效应的波-流和海洋结构物相互作用的全非线性模拟研究

项目编号： No.51279179

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 水利工程

项目作者： 王赤忠

作者单位： 浙江大学

项目金额： 70万元

中文摘要： 在实际海洋环境中，波浪和水流通常是同时存在的。波-流联合作用不仅影响海洋结构物的受力和运动，其产生的水动力载荷甚至会导致结构物受到破坏从而影响其安全性。恶劣海况下波浪的非线性特性很强且水流的速度较大，其与结构物作用时的粘性效应和涡旋效应显著，传统的基于势流的线性、二阶甚至全非线性理论均不适于求解此类问题。本研究采用任意拉格朗日-欧拉有限元法来对海洋结构物如张力腿平台和波-流的全非线性相互作用问题进行数值模拟和试验研究，直接求解Navier-Stokes方程，采用若干组不同参数的波浪（波高、波浪频率和传播方向不同）以及不同参数的水流（流速和方向不同）来计算结构物处的波浪爬高及作用在结构物上的水动力载荷及相应运动响应，同时分析水流和波浪的相互影响，为张力腿平台等海洋结构物的设计和安全运行提供技术支撑。本研究的结果将通过和试验及其它数值方法如时域二阶理论的计算结果进行对比来验证计算方法的有效性。

中文关键词： 波-流相互作用；非线性波；海洋结构物；粘性效应；任意拉格朗日-欧拉有限元法

英文摘要： Waves and currents usually coexist in real ocean environment. The wave and current not only affect the hydrodynamic forces on ocean structures such as TLPs and their corresponding motions, but also may destroy these structures and hence cause some problems on safety. The wave has stronger nonlinear features and the current velocity is larger in severe ocean environment, and the viscous and vortex effects are clear when they act on the ocean structure. The linear, second order or even the fully nonlinear theory are not suitable for this situation. We employed an arbitrary Lagrangian-Euler finite element method to solve the Navier-Stokes equation for studying interactions between the wave-current and the ocean structure, and a group of wave parameters (wave heights, wave frequencies and their propagation directions) and current parameters (current velocities and directions) are used in the present study for calculating wave runups along the structure and analyzing the mutual influence on each other for the wave and the current, which may provide technical support for the design of ocean structures. We will make comparisons between the fully nonlniear results and the previous linear and second order solutions to validate the efficiency of the present numerical method.

英文关键词： wave-current；nonlinear wave；ocean structure；viscious effect；ALE finite element method