传热管在内外流体作用下的振动特性研究

为研究传热管在内外流体共同作用下的动力学行为,引入尾流振子模型,同时考虑轴向伸长引起的几何非线性的影响,建立了弹性管-内外流体耦合系统的分析模型,并利用Galerkin方法离散非线性耦合方程。基于数值计算,分析了内外流体流速、几何非线性参数对传热管振动响应的影响,得到了传热管在后屈曲时的分叉图、相图。结果显示,传热管在后屈曲时会表现出一系列丰富的动力学行为,如倒分叉、周期运动和混沌运动。

Vibration Characteristics of Heat Transfer Tube Subjected to Internal and External Flows

In order to investigate the dynamic behavior of heat transfer tube under the influence of both internal and external flows,an analytical model of the coupling system was developed.The wake oscillator model was introduced to present the analytical model.Meanwhile,the mean axial extension of the tube was also considered.The nonlinear coupled equations of motion were discretized by employing the Galerkin method.Based on numerical simulations,the effects of internal and external fluid flow velocities and nonlinear parameters on response were studied.Moreover,the bifurcation diagram and phase portrait for vibration amplitude with various external fluid velocities were constructed.The results show that the tube displays various dynamical behaviors around the post-buckling configuration such as inverse period-doubling bifurcation,periodic and chaotic motions.