利用高阶边界元方法建立模拟聚焦波浪与弹性浮板作用的完全非线性二维时域数值水槽模型,其中指定2阶Stokes速度解析解产生聚焦波;采用混合欧拉拉格朗日方法追踪流体和结构表面变化,再利用梁自由振动的自然模态函数近似流固交界面的瞬时位移;使用4阶RungeKutta法更新水面及浮板位移和速度势.对比发现,该数学模型可以准确地模拟浮板在波浪作用下的水弹性响应和所期望的聚焦波浪.并进一步研究了浮板摆放条件、浮板厚度、聚焦波频率带宽和入射波幅对浮板水弹性响应的影响.
This paper establishes a twodimensional fully nonlinear numerical wave tank for studying the interaction between focused waves and floating elastic plate. The secondorder Stokes wave velocity is given to generate the input wave. The mixed EulerianLagrangian approach is applied to track the transient free and plate surface. A series of modal functions with freeend conditions are adopted to interpolate the displacement, and then the fourthorder RungeKutta scheme is used to refresh profile and velocity potential. The numerical model is verified with existing numerical and experimental results. The effects of the design parameters on the responses are systematically analyzed.
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