摘要
研究不同边界条件下光滑、正交加筋圆柱壳-球壳组合结构的自由振动。通过对圆柱壳与球壳连接处简化处理,视球壳为自由约束,圆柱壳为简支约束,据Flügge薄壳理论利用Rayleigh-Ritz法求得结构频率,与有限元软件ANSYS结果比较,验证该方法的适用性及有效性;分析球壳扁率及组合壳体长径比对频率影响。结果表明,球心半角Φ增大结构自振频率降低;长径比L/Rc增大球心半角Φ对组合结构频率影响逐渐减弱,结构自振频率逐渐降低,且降幅减小。
The free vibration of a joined, smooth and orthogonally stiffened cylindrical-spherical shell under various boundary conditions was studied.Based on the simplification of the joined part,the spherical shell is of free boundary condition and the cylindrical shell is of simply supported boundary condition.The Rayleigh-Ritz method was applied to solve the natural frequencies of the structure according to the Flugge＇s thin shell theory.The natural frequencies were calculated and compared with those by the finite element software ANSYS to confirm the applicability and validity of the simplification.The effects of the shallowness of the spherical shell and the length-to-radius ratio of the joined shell on the free vibrational behavior of the joined structure were investigated.The results indicate that as the semi-angle Φof the sphere increases,the natural frequencies decrease.As the length-to-radius ratio L/Rc increases,the influence of the semi-angle Φof the sphere on the natural frequencies decreases,the natural frequencies decrease gradually and their reducing magnitude descends.
出处
《振动与冲击》
EI
CSCD
北大核心
2015年第22期129-137,共9页
Journal of Vibration and Shock
基金
国家自然科学基金项目(51278511)
