Dynamic Characteristics of Conveying Fluid Pipe Under Thermal Load and Axial Force by Galerkin-Eigenvalue Method

This paper examines the effects of axial force and temperature changes on the dynamic characteristics of pipes. The Galerkin method, combined with the eigenvalue method, is employed to solve the fluid–structure interaction (FSI) motion equations for the pipe. The study investigates the impact of axial force, temperature changes, fluid velocity, fluid pressure, and pipe structure parameters on the pipe’s natural frequency. Numerical results reveal that different parameters have varying effects on the pipe’s natural frequency, leading to the determination of stability conditions’ varying influences. Combined with the finite element method (FEM), the impact of temperature changes on the pipe’s natural frequency is analyzed. The correctness of the numerical results of the Galerkin-eigenvalue method was verified through comparative methods. The research results confirm that this numerical method provides strong theoretical support for analyzing the nonlinear dynamic characteristics of pipelines under temperature changes in random vibration environments. This is of guiding significance to the vibration reduction design of the pipeline system and helps prevent and reduce the structural damage and accident risks caused by the change in the pipeline’s dynamic characteristics.