环肋圆柱壳的自由振动特性

Free Vibration Characteristics of Ring-stiffened Cylindrical Shells

研究了环向肋骨沿壳体轴向任意布置、无横向偏转的环肋圆柱壳自由振动特性。基于Sander壳体理论,采用Rayleigh-Ritz能量法推导出环肋圆柱壳自由振动的固有频率特征方程。经过与各向同性圆柱壳的固有频率进行对比,验证了本文研究的有效性和正确性,计算了两端简支与一端固支一端自由等不同边界条件下壳体的固有频率,分析了加肋位置及边界条件对圆柱壳振动频率的影响。研究结果表明:加肋对圆柱壳的固有频率有显著提高,两端简支边界条件下的频率大于一端固支一端自由边界条件的频率;肋骨位置对于频率的影响明显,主要表现在壳体长度与半径比值较小、壳壁厚度与半径比值较大的情况下。

The vibration characteristic of cylindrical shells with ring supports was studied in this paper. The intermediate supports of the shell were arbitrarily placed along the shell without the lateral deflection. By using Sander shell theory,the shell eigenvalue governing equation was derived based on the Rayleigh-Ritz method. The analysis was validated by comparing the results with those in the literature. The vibration characteristics were obtained from two different boundary conditions with SS-SS and C-F as the examples. The influences of ring support position and the boundary condition on cylindrical shell vibration were analyzed. It is found that ring support has significant contribution to the frequency,and that the frequency with SS-SS is higher than that with C-F. Ring support position has big influence on the frequency with small L / R ratio and large h / R ratio.