基于双向流固耦合的大直径掩埋管道强度研究

Research on the Strength of Large Diameter Buried Pipeline Based on Bidirectional Fluid-solid Coupling

针对大直径掩埋管道工作中发生的管道结构变形问题,综合考虑管内流体与结构之间的耦合,通过双向流固耦合方法求解管内流体Navier-Stokes(简称:N-S)方程和管道结构运动方程,分析不同工况下管道变形和应力的变化规律。结果表明:管道在竖直方向上的变形量最大,且管道的弯管部位变形量也较大;管道的应力主要集中在入口和出口位置,出口的最大应力是入口的1.45倍;弯管的最大变形集中在管道外侧,最大应力集中在管道内侧,弯管的内外表面的变形和应力基本相同;管道整体和弯管局部的最大变形和最大应力都随流体压力的增大非线性增大。该方法为计算大直径掩埋管道的结构设计提供了有价值的参考。

Aiming at the problem of pipeline structural deformation that occurred during the work of large-diameter buried pipelines.Comprehensive consideration of the coupling between the fluid in the pipe and the structure.The two-way fluid-solid coupling method is used to solve the N-S equation of the fluid in the pipe and the movement equation of the pipe structure,and analyze the change law of pipe deformation and stress under different working conditions.The results show that the deformation of the pipeline in the vertical direction is the largest,and the deformation of the elbow of the pipeline is also large.The stress of the pipeline is mainly concentrated at the inlet and outlet positions,and the maximum stress at the outlet is 1.45 times that of the inlet.The maximum deformation of the elbow is concentrated on the outside of the pipe,the maximum stress is concentrated on the inside of the pipe,and the deformation and stress of the inner and outer surfaces of the elbow are basically the same.The maximum deformation and maximum stress of the entire pipeline and the local elbow are nonlinearly increased with the increase of fluid pressure.This method provides a valuable reference for calculating the structural design of large-diameter buried pipelines.