端部约束悬臂输流管道的动力学特性

根据梁模型横向弯曲振动模态函数一般表达式,由边界约束条件确定其模态函数的一般表达式,采用Galerkin法将运动方程在模态空间内展开,利用动力学分析方法,分析端部受线性弹簧支承和扭转弹簧约束的端部约束悬臂管道从非保守系统逐渐变为保守系统过程中的固有特性和稳定性。数值仿真结果表明,这种特殊边界输流管道具有复杂变化的动力学特性,支承和约束刚度系数的变化对系统固有特性和稳定性产生很大的影响:随着弹簧刚度的增大,系统的固有频率上升,管道失稳方式从颤振变为屈曲,并且影响系统其他参数对管道动力学特性的作用。

DYNAMICAL BEHAVIORS OF RESTRAINED CANTILEVER PIPE CONVEYING FLUID

The dynamical characteristics of the restrained cantilever piping system constrained by a linear and torque spring at its free end are studied.The expression of vertical vibration mode-function of the restrained cantilever pipe system was derived from its boundary conditions based on the corresponding beam model.The equation of motion was discretized by Galerkin method.The natural characteristics and stability from non-conservative system to conservative system of this restrained cantilever pipe were analyzed by use of dynamical methods.The stimulation results shows that this special boundary piping system involves complicated dynamic characteristics.The supporting and constraining elastic coefficients have great effect on systematical natural frequency and stability,the systematical frequency varies with elastic coefficients,and instability way changes from flutter to divergence and influences other systematical parameters on dynamical characteristics of the piping system.