摘要
输流管道内流体的脉动是造成管道系统失稳的重要因素。对于环状流虽然气、液两相速度相差很大,但液相介质流动特性对管道振动特性的影响不容忽视。为了分析环状流液相介质的脉动对管道非线性振动的影响,建立了管道横向振动模型。模型方程利用Galerkin法进行离散,同时采用四阶Runge-Kutta迭代方法求解。分析了包括固有频率、临界气速、分岔、混沌等基本动力学特征。研究结果表明,表观液速增加不仅导致系统固有频率显著下降而且使得系统的临界气速下降。当不考虑液相脉动时,只观察到Pitchfork分岔,表观液速由0.2 m/s增加到0.9 m/s过程中分岔起点由31.9 m降低到21.8 m。当液相介质脉动时,管道系统随着脉动频率增加检测到包括多种形态的周期运动、概周期运动以及混沌等振动形态。研究结果对于工程具有指导意义。
Pulsation of fluid in pipeline is an important factor to cause instability of pipeline system.For annular flow,although there is a large difference between gas and liquid phase velocities,effects of liquid phase medium flow characteristics on pipeline vibration characteristics can't be ignored.Here,to analyze effects of pulsation of annular flow liquid phase medium on pipeline nonlinear vibration,a transverse vibration model of pipeline was established.The model equations were discretized using Galerkin method and solved using the 4th Runge-Kutta iteration method to analyze basic dynamic characteristics including natural frequency,critical gas velocity,bifurcation,chaos,etc.The study results showed that increase in apparent liquid velocity not only causes significant decrease in system natural frequency,but also causes decrease in system critical gas velocity;when not considering liquid phase pulsation,only Pitchfork bifurcation is observed,and bifurcation starting point decreases from 31.9 m to 21.8 m in process of apparent liquid velocity increasing from 0.2 m/s to 0.9 m/s;when liquid phase medium pulsating,pipeline system's various vibration forms of periodic motion,quasi-periodic motion and chaos are detected with increase in liquid pulsation frequency;the study results have guiding significance for engineering.
作者
周云龙
米列东
ZHOU Yunlong;MI Liedong(School of Energy and Power Engineering,Northeast Electric Power University,Jilin 132012,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2023年第21期119-125,159,共8页
Journal of Vibration and Shock
关键词
环状流
固有频率
临界气速
分岔
混沌
annular flow
natural frequency
critical gas velocity
bifurcation
chaos
