【摘要】 主要介绍目前容器类流固耦合模态分析最常用的两种计算方法:声固耦合法及虚拟质量法。从理论上分别对这两种方法进行分析,并指出它们之间的联系与区别:虚拟质量法采用了声固耦合法在不可压缩流体情况下的形式,并有所改进,即流体的作用完全由虚拟质量阵来体现,而流体的虚拟质量阵则通过具有解析解性质的边界元法获得。最后,通过开口方槽干状态、湿状态的无阻尼模态仿真分析研究,揭示出流体对结构模态特性影响的变化规律,同时指出了两种方法(虚拟质量法、声固耦合法)对结构湿模态计算结果有规律性的差异:随着振动频率的升高,不仅容器内流体对结构模态特性的影响在减小,分析湿模态的两种方法所得到的计算结果之间的差别也在逐渐减小。更多还原

【Abstract】 Two conventional algorithms for fluid-structure coupling modal analysis of the liquid filling containers are mainly introduced in this paper.They are coupled acoustic-structural analysis(CASA) and virtual fluid mass(VFM).It points out the relation and difference between the two algorithms through the theory analysis.VFM adopts the incompressible liquid form that appears in CASA,in which some progress has been made,namely,the effect of the fluid is incarnated completely by virtual mass matrix,and the virtual mass matrix of the liquid is obtained by the boundary element method(BEM) with the property of analytic solution.Based on the study on the dry modes and the wet modes of one ringent box,the varying laws of influence of the liquid on the structure modal characteristics are revealed.At the same time,the study result indicates the well-regulated otherness between the wet modes results from the two methods(VFM and CASA):with increase in vibration frequency,not only the effect of liquid on the structure dynamic characteristic decreases gradually,but also the difference between the two methods decrease.更多还原