温度对裸露的输气管道固有频率的影响

The Influence of Temperature on Natural Frequency of Exposed Gas Pipeline

以采空区埋地管线系统为研究对象,讨论了其裸露在自然环境中时,温度变化对输气管道振动特性的影响。本文利用达朗贝尔原理和考虑温度变化的本构关系建立了输气管道振动微分方程,以两端简支管道为例利用里兹法求解其固有频率,进而分析温度对输气管道固有频率的影响。研究结果表明:温度对管道低阶固有频率影响不大,对高阶固有频率影响较明显;随着裸露长度和壁厚的增加,温度对管道固有频率影响加剧;输气管道固有频率随温度变化值增大而减小。研究结果可为管道设计提供参考。

The buried pipeline system in mined out areas is studied in this paper.The effect of temperature change on the vibration characteristics of gas pipeline is discussed when it is exposed to natural environment.The vibration differential equation of gas pipeline is established using the principle of d’Alembert and the constitutive relation considering temperature change.Taking the pipe at two simple supported ends as an example,its natural frequency is solved using the Ritz method,and the influence of temperature on its natural frequency is analyzed.The results show that,temperature has the lesser influence on the lower order natural frequencies and the more influence of the higher order natural frequencies.With the pipe bare length or wall thickness increasing,the influence becomes more remarkable.The natural frequencies of the pipe will become the lower with the increasing temperature.The results can provide the technical support for pipeline design,the safety check and risk assessment on the active pipeline.