A system of two coupled oscillating structures may experience dynamical synchronization under coupling effects. Dynamical synchronization refers to the process in which two vibrating structures under coupling effects may display similar dynamics and vibrational behaviors even though their important parameters are not equivalent. In this study, the three-dimensional dynamics and synchronization behaviors of two coupled fluid-conveying pipes connected with linear springs are investigated. In the analytical model, the geometric nonlinearities due to axial elongation of the two pipes and the extension of linear springs are considered. The flow velocities of the internal fluid of the two pipes may be steady or pulsatile. In the case of the flow velocities of the two pipes being steady, the lowest several natural frequencies and the post-buckling behavior of the two-pipe system are obtained by changing the flow velocities in the two pipes. When one pipe conveys pulsatile fluid and the other conveys steady fluid, the dynamical bifurcation and synchronization behaviors of the two-pipe system are analyzed, with several typical synchronization patterns being explored by means of time traces, phase portraits, power spectral density (PSD) diagrams, Poincaré maps, etc. It is shown that making use of synchronization characteristics of the two-pipe system may provide a possible way to control the vibrations of the two-pipe system and to achieve some special engineering objectives.

两个耦合振荡结构的系统可能会在耦合效应下经历动态同步。动态同步是指在耦合作用下的两个振动结构，即使它们的重要参数不等价，但仍可能表现出相似的动力学和振动行为的过程。在这项研究中，研究了与线性弹簧连接的两个耦合流体输送管道的三维动力学和同步行为。在解析模型中，考虑了由于两根管道的轴向伸长和线性弹簧的伸长引起的几何非线性。两个管道的内部流体的流速可以是稳定的或脉动的。在两管流速稳定的情况下，通过改变两管中的流速，得到了两管系统的最低几个固有频率和后屈曲行为。分析了一个管道输送脉动流体、另一管道输送稳定流体时两管系统的动态分岔和同步行为，通过时间轨迹、相图、功率谱密度（PSD）探索了几种典型的同步模式图、庞加莱图等表明，利用双管系统的同步特性可以为控制双管系统的振动和实现一些特殊的工程目标提供可能的途径。