结构中频振动分析的混合方法

摘要

针对结构振动的中频问题，提出了一种新的混合分析方法。具有低模态密度的子结构利用有限元建模，高模态密度子结构利用波动方法建模，并利用边界处的位移连续和力平衡条件进行求解。以耦合梁结构为例，给出了具体的计算过程，通过解析方法进行了仿真验证。结果表明了此混合方法的有效性。进一步地计算了高频子结构的能量密度响应，并且通过对比说明，此方法在计算边界位置的能量密度响应时可以得到精确度更高的结果。%A new hybrid method was presented to predict vibration responses of structures in medium frequency. Finite element method was used to model subsystems with low modal density while wave method was for subsys-tems with high modal density.A coupled-beam system was exemplified to demonstrate the details.Compared with the analytical method,simulation results validate the hybrid method.Energy density response was obtained for the subsystem with high modal density.It is found that the hybrid method produces a more precise prediction in the vicinity of boundaries.