溃坝水流冲击弹性板模型试验与数值模拟  

Model testing and simulation analysis of an elastic plate impacted by dam failure-induced water flow

作　　者：张建伟 王兵鹏 侯鸽 ZHANG Jianwei;WANG Bingpeng;HOU Ge(College of Water Conservancy,North China University of Water Resources and Hydropower,Zhengzhou 450046,China)

机构地区：[1]华北水利水电大学水利学院,河南郑州450046

出　　处：《水科学进展》2024年第6期993-1004,共12页Advances in Water Science

基　　金：国家自然科学基金资助项目(52279133)。

摘　　要：研究流固耦合(FSI)问题对于准确预测水流与结构之间的相互作用具有十分重要的意义。基于光滑粒子流体动力学(SPH)方法建立溃坝水流冲击弹性板数值模型,通过物理模型试验和有限元法(FEM)多角度验证SPH模型的有效性和优越性,通过分析流场的性质、流固作用力以及结构的频谱变化规律,进一步剖析自由表面流冲击下流固耦合本质特征。结果表明:①水流之间速度的跳跃和自由液面的强曲率导致在水流空腔处产生涡旋;②水流翻越弹性板时产生顺时针涡量,当撞击壁面的水流再次接触弹性板时由于流速的不同而产生逆时针涡量;③水流冲击下流固作用力呈现出先增大后减小再增大的变化趋势,弹性结构变形越小受到的力越大;④弹性结构固定端沿自由端振动频率逐渐降低,弹性板自由端变形越大其振动响应越弱,其一阶频率由2.88 Hz减至2.44 Hz,二阶频率由6.24 Hz减至5.68 Hz,三阶频率由9.57 Hz减至8.96 Hz。The study of fluid-structure interaction(FSI)problems in elastic structures is crucial for accurately predicting the coupling between water flow and structural behavior in hydraulic engineering.A numerical model of an elastic plate impacted by dam failure-induced water flow is established using the smooth particle hydrodynamics(SPH)method.The validity and advantages of the SPH model are verified through physical model tests and comparisons with the finite element method(FEM)from multiple perspectives.Building on this foundation,the characteristics of fluid-structure interaction under the impact of free surface flow are further analyzed by examining the flow field properties,flow-structure forces,and the structural spectral variation patterns.The results indicate the following:①A velocity jump between the water flow and the sharp curvature of the free liquid surface leads to vortex formation at the cavity.②The water flow over the elastic plate generates clockwise vorticity,while the water flow that hits the wall and re-contacts the elastic plate creates counterclockwise vorticity due to the difference in flow velocity.③The force exerted by the water flow on the structure shows a pattern of increasing,then decreasing,and increasing again,with smaller deformation of the elastic structure corresponding to greater force.④The vibration frequency along the elastic structure decreases gradually from the fixed end to the free end.Larger deformation of the free end weakens the vibration response,with the first-order frequency decreasing from 2.88 Hz to 2.44 Hz,the second-order frequency from 6.24 Hz to 5.68 Hz,and the third-order frequency from 9.57 Hz.to 8.96 Hz.These findings provide valuable insights and guidance for addressing fluid-structure coupling problems.

关 键 词：流固耦合 溃坝水流 振动响应 光滑粒子流体动力学 

分 类 号：TV122[水利工程—水文学及水资源]