不同流体加速度描述对输液曲管稳定性的影响

Effects of different fluid accelerations on stability of curved pipes conveying fluid

在自然坐标系中建立了具有任意初始构型可伸长输液曲管的数学模型并进行了数值模拟。为了便于处理边界条件,引入新的独立变量,采用微分求积法(Differential Quadrature Method,DQM)和分块矩阵的方法求解输液曲管的固有频率。讨论了三种流体加速度表示方法对可伸输液管道稳定性的影响。研究发现,对复杂构型的输液曲管,三者的第一阶固有频率随着流速的增大,差别越来越显著;然而,对于规则构型的输液管道,结果却非常相近。

A dynamic model of an extensible curved pipe with an arbitrary initial configuration was established in an arc coordinate system and its numerical simulation was performed afterwards. A new independent variable was introduced to deal with boundary conditions in order to obtain natural frequencies of curved pipes conveying fluid based on the differential quadrature method（ DQM） and the partitioned matrix method. The effects of three fluid accelerations on the stability of the pipes conveying fluid was discussed. It was shown that with increase in fluid velocities,the differences between the first natural frequencies of pipes with complex configuration under three different fluid accelerations become more significant; however,for regular configuration pipes,the effects of different fluid accelerations on pipes＇ natural frequencies are small.