变截面输流管道防共振可靠性分析

摘要

采用Euler梁模型建立了变截面管道的振动控制方程, 在充分考虑流速和截断系数的影响下, 利用动刚度矩阵法进行了近似求解, 求得了变截面管道固有频率以及管道失稳的临界流速.根据管道的前两阶固有频率建立了防共振可靠性功能函数, 利用主动学习Kriging方法计算出不同流速工况及不同截断系数工况下的一阶和二阶共振失效概率, 分析出流速与截断系数对共振失效的影响.%Considering the liquid velocity and the diameter variation coefficient, the Euler-Bernoulli beam model is used to set up the vibration control equation. Dynamic stiffness method is applied to solve the equation approximately, and then the natural frequencies and critical velocity of the variable diameter pipe conveying fluid are obtained. According to the first two order natural frequencies, the anti-resonance reliability performance function is established, first and second order resonance failure probabilities are calculated under the different section variation coefficients and fluid velocities based on the Active Learning Kriging method. Effects of velocity and diameter variation coefficient on resonance failure are analyzed.