Finite Element Analysis of Stresses in Pipeline Joints Using Open Source Software

The paper presents the results of numerical simulation using the finite element method (FEM) in the FreeCAD environment, confirming the hypothesis about the occurrence of a stress singularity in an L-shaped bend of a pipeline. The study was conducted on two three-dimensional models: a smooth pipe connection with a break in the curvature of the axis and an angular connection with an infinitely large curvature at the junction. The developed FEM algorithm made it possible to simulate both types of connections in a single three-dimensional geometry. The critical radius of curvature was found, at which the stresses in the smooth connection model reach the level of stresses in the angular connection model. The numerical simulation results presented in the article demonstrate the influence of the connection geometry on the stress distribution and confirm the presence of a singularity in smooth connections with small radii of curvature. The work contributes to the development of stress analysis methods in complex pipeline systems.

Keywords

stress singularity; L-bend; finite element method; FreeCAD; numerical simulation; pipelines.

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