组合管道结构流固耦合振动特性分析

In order to study the vibration characteristics of the pipeline structure under fluid-structure coupling, the natural frequencies and modal shapes of the combined pipeline structure with and without liquid were obtained by test and simulation analysis. Based on the bidirectional fluid-structure coupling analysis method, the flow induced vibration response and fluid pressure change of the pipeline are solved, and the dynamic response test is carried out to compare with the numerical results. The results show that the natural frequency of the pipeline is obviously reduced under the influence of the additional mass of the fluid, but the modal shape is basically not affected. The presence of discontinuous parts such as straight bend joint and elbow in combined pipeline structure will cause the fluid state in the pipe to be disturbed and the pressure will fluctuate and induce pipeline vibration, and the vibration frequency of the pipeline is close to its natural frequency. The research results have important guiding significance to ensure the safe operation of pipeline system.