变截面输液管道流固耦合振动特性研究

摘要

In order to analyze the vibration character of the stepped pipe conveying fluid, the vibration characteristic of stepped pipe, based on the 4-equations model of fluid-structure interaction, was studied by wave propagation approach in this paper. The reflection model of vibration wave at all kinds of supports and the reflection/transition model at the stepped cross section were established based on the continuity and force balance condition, respective- ly. The validation of the proposed method was verified through the analysis of critical velocity. As an example, a piece of pipe simply supported at both ends with stepped section at the middle point was investgated. The vibration characteristic equation was developed in terms of wave-train closure principle. Finally, the graphs of natural frequency distribution were obtained for four different cases. The results show that the proposed method is much effective and easy to programming.%为了研究变截面输液管道的流固耦合振动特性，从管道流固耦合振动的4方程模型出发，应用波传播方法对变截面管道的振动进行了研究。建立了振动波在各种支撑端部的反射模型和管道截面突变处的反射和透射模型；通过计算管道的临界流速，验证了所建立模型的正确性。以一段两端简支中间截面突变管道为例，根据波循环原理，建立了其振动特征方程；最后，得到了4种不同工况下截面突变管道的固有频率。算例分析表明，本文提出的方法计算效率高，易于编程。