水下环肋圆柱壳的振动耦合频率影响因素分析

Influence Foctors Analysis of Vibration Coupling Frequency of Submerged Ring Stiffened Cylindrical Shell

在Flügge理论的基础上,考虑流体的影响,通过波动法推导出静水压力下环肋圆柱壳耦合振动特征方程,并利用牛顿迭代法求得耦合振动频率。将静水压力下圆柱壳与环肋圆柱壳的计算结果进行了对比,验证了本文方法的正确性和有效性。通过算例分析了在不同边界条件下,环肋形式、静水压力、圆柱壳尺寸、环肋尺寸和环肋数目等因素对静水压力下环肋圆柱壳耦合频率的影响。研究结果表明:在静水压力下,肋条的存在增强了圆柱壳的振动强度,耦合作用的存在降低了圆柱壳的振动强度。连续静水压力下,随着静水压力的增大,圆柱壳的振动强度不断减弱;圆柱壳尺寸、肋条尺寸和环肋数目的改变在不同程度上改变了圆柱壳的耦合频率。

Based on the Flügge theory and considering the liquid influence,the coupled vibration characteristic equation of ring stiffened cylindrical shell under hydrostatic pressure was derived via wave method. The natural frequency of the coupled vibration was obtained by the Newton iteration method. Compared the calculation results of the submerged cylindrical shell with calculation result of the ring-stiffened shell under hydrostatic pressure,the correctness and validity of research method in this paper was verified. By numerical examples,the effects of ring type,hydrostatic pressure,shell size,ring size and ring number on the coupling frequency of the ring stiffened cylindrical shells under different kinds of boundary conditions were illustrated. The results shows that the ring-stiffener reinforces the vibration intensity of the cylindrical shell under hydrostatic pressure. The coupling effect weakens the vibration intensity of the cylindrical shell. The vibration strength of cylindrical shell is weakened with increasing hydrostatic pressure. The coupled frequencies are different with different shell dimensions,ring-stiffener dimensions and numbers.