Parametric study of a linear elastic pipeline under in-plane bending

This example demonstrates the ability of elbow elements to model the nonlinear response of initially circular pipes and pipebends accurately when the distortion of the cross-section by ovalization is significant. It also provides some guidelines on the importance of including a sufficient number of Fourier modes in the elbow elements to capture the ovalization accurately. In addition, this example illustrates the shortcomings of using “flexibility knockdown factors” with simple beam elements in an attempt to capture the effects of ovalization in an ad hoc manner for large-displacement analyses. Similar analyses involving pipe elements in Abaqus/Explicit are included.

This page discusses:

See Also
In Other Guides
Pipes and Pipebends with Deforming Cross-Sections: Elbow Elements

ProductsAbaqus/StandardAbaqus/Explicit

Elbows are used in piping systems because they ovalize more readily than straight pipes and, thus, provide flexibility in response to thermal expansion and other loadings that impose significant displacements on the system. Ovalization is the bending of the pipe wall into an oval—i.e., noncircular—configuration. The elbow is, thus, behaving as a shell rather than as a beam.