基于波传播法的水下圆柱壳临界载荷-频率特性分析

基于振动的水下圆柱壳临界载荷的预报具有结构无损的优势。针对基于振动的数值仿真及振动试验预测方法存在的不足之处,提出了基于波传播法的水下圆柱壳失稳载荷的理论求解方法。建立了计及静水压力影响的水下圆柱壳固-液耦合振动方程,基于波传播方法获得耦合系统的频率方程。运用Muller三点迭代法求出水下圆柱壳的固有频率,通过线性拟合的方法求出水下圆柱壳临界载荷的弹性理论解,修正后可得到便于工程应用的临界载荷。结果对比表明了该方法的准确性,且具有方法简便、计算量小和易于参数优化的优点。

Frequency Characteristics Analysis for Critical Load of a Submerged Cylindrical Shell Based on Wave Propagation Approach

This study presents an approach,which is nondestructive,to predict critical hydrostatic pressure of a submerged cylindrical shell.The structural-fluid coupling characteristic equation of the system is established based on wave propagation approach.The data of natural frequencies of the system under different hydrostatic pressures is obtained after solving the coupled equation.The curve of squared natural frequency versus hydrostatic pressure is then drawn with the data.Critical hydrostatic pressure is obtained by means of fitting the curve.The results obtained from present approach show good agreement with those from classical theory.