加筋圆柱壳机械导纳分频段计算方法

针对工程中常用的加筋壳结构,提出一种分频段计算加筋壳机械导纳的新方法.根据加强筋在不同频段对壳体振动特性影响规律的不同,将加筋壳在低频、中频和高频分别等效为各向异性壳、各向同性壳以及无限长壳.将分频段计算结果与子结构模态扩展法比较,结果显示:两种方法计算结果吻合较好,验证了分频段计算方法的有效性.在计算工程实际结构时,此计算方法相比子结构模态扩展法,可以获得加筋板机械导纳的显式表达式;此方法的提出为后续分析更为复杂的加筋耦合结构振动传递特性提供了理论基础.

A new computing method for Mobility of Rib-stiffened shell in different frequency bands

A new method is developed for computing the mobility of rib -stiffened cylindrical shell in different frequencies. The cylindrical shell to orthotropic shell, isotropic shell and infinite shell separately in different frequency bands is equivalented according to the different effects of ribs for shell. Numerical results are compared with results based on model expansion technique. The compared results confirm the effectiveness of the new method in this paper. However, comparing with model expansion technique, the apparent computing formulas can be obtained using the new method. Meanwhile, it saved the mode information in low and middle frequency bands. The new method can provide theoretical bases for further more complex rib -stiffened structures.