平板流固耦合振动的数值分析  

Numerical Analysis of Fluid-structure Interaction Vibration for Plate

作　　者：胡世良[1] 鲁传敬[1,2] 何友声[1,2] 

机构地区：[1]上海交通大学工程力学系,上海200240 [2]上海交通大学水动力学教育部重点实验室,上海200240

出　　处：《上海交通大学学报》2013年第10期1487-1493,1502,共8页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金(10832007)资助项目;上海市重点学科(B206)资助项目

摘　　要：采用了一种基于紧耦合的流固耦合算法,对流场与柔性平板之间的耦合运动进行了数值模拟.流场部分通过有限体积法求解任意拉格朗日-欧拉描述下的不可压缩N-S方程,而结构则由有限元法离散求解拉格朗日坐标下的弹性动力学方程.在一个时间步内,流场与结构计算区域的交界面上进行多次的数据传递和插值,以保证满足耦合面边界条件.计算了在静止流场中弹性板的自由振动和方柱后部平板的涡激振动现象,监测了平板的振幅和频率以及水动力载荷.通过与前人结果的比较,验证了所采用的流固耦合算法的可靠性.同时,分析了不同的材料参数对于平板耦合运动的影响.流体黏性越大对平板振动的阻尼作用越明显,而流体密度的增加会加速振动的衰减,并降低振动的频率.对于具有较低固有频率的结构,在耦合运动中的振动幅度和频率也较小.A numerical approach of a fluid-structure coupling with closely coupled algorithm was used to simulate the coupling motion between the fluid and the flexible plate. The fluid, which was modeled by the Arbitrary Lagrangian-Eulerian （ALE） formulation of the incompressible Navier-Stokes equations, was simulated by the finite volume method. The structure was described by the equation of the elastodynamics in Lagrangian representation, and was simulated using finite element approach. In order to satisfy the cou- pling interfacial boundary condition, the date transfer and interpolation was performed via the interface of the fluid and structure several times within one time step. The free oscillation of elastic plane in resting fluid and the VIV of flat plane behind the square head was calculated, and the amplitude and frequency of the plate vibration and the hydrodynamic load on the plate were monitored. The validity of the coupling method used in this paper was verified by comparing it with the previous work. Meanwhile, the influence of material parameters on fluid-structure interaction motion was analyzed. It was noted that larger viscosi- ty of fluid damps had a more significant influence on the vibration amplitude of the plate more obviously. And with the increase of fluid density, the attenuation velocity of the vibration increased, while the frequency decreased. When the structure had low natural frequency, the amplitude and frequency of the coupiing motion would also be small.

关 键 词：流固耦合 紧耦合 任意拉格朗日-欧拉描述 

分 类 号：O351.2[理学—流体力学]