输液管道动态稳定性研究

将输液动力管道简化为梁模型,建立管道的侧向振动微分方程,研究管道的动力特性。采用Herm ite插值函数和Galerkin法离散得到其有限元的标准形式。在有阻尼和无阻尼两种状态下,分别研究了当管内流为恒定流时管道长度、管内流速、管道终端压强对管道动力特性的影响。在管内流速度和管道终端压强含有谐波扰动的情况下,得到管道固有频率的变化规律。研究表明,跨距增加、流速变大、压力上升都会降低管道的固有频率,增加管道失稳的可能。这些管道动力参数的获得对管道跨距的合理设计、支撑阻尼处理、管道稳定性的提高具有实际意义

Study on Dynamic Stability of Pipes Containing Flowing Fluid

This paper describes the dynamics and stability of pipes containing flowing fluid . Clarified as a girder, the lateral motion equation of the pipe is derived. Hermite interpolation function and Galerkin method are adopted to decentralize the equation. Focus is devoted to the relationship between dynamic characteristics of pipe with pipe span, constant inner flow velocity, inner velocity with harmonic component, and pressure at downstream end, with and without viscous damping respectively. The result indicates viscous damping can serve to decrease the extent of instability, and that the natural frequency of pipe decreases as the pipe span, the flow velocity and the downstream pressure increase. It also shows that the harmonic component of inner fluid and downstream pressure can cause harmonic fluctuation of the natural frequency of pipe, with amplitude determined by the extent of the interference.