Isogeometric Collocation: A Mixed Displacement-Pressure Method for Nearly Incompressible Elasticity


Date

2021-11-25

Publication Type

Journal Article

ETH Bibliography

yes

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Data

Abstract

We investigate primal and mixed u−p isogeometric collocation methods for application to nearly-incompressible isotropic elasticity. The primal method employs Navier’s equations in terms of the displacement unknowns, and the mixed method employs both displacement and pressure unknowns. As benchmarks for what might be considered acceptable accuracy, we employ constant-pressure Abaqus finite elements that are widely used in engineering applications. As a basis of comparisons, we present results for compressible elasticity. All the methods were completely satisfactory for the compressible case. However, results for low-degree primal methods exhibited displacement locking and in general deteriorated in the nearly-incompressible case. The results for the mixed methods behaved very well for two of the problems we studied, achieving levels of accuracy very similar to those for the compressible case. The third problem, which we consider a “torture test” presented a more complex story for the mixed methods in the nearly-incompressible case.

Publication status

published

Editor

Book title

Volume

129 (3)

Pages / Article No.

1125 - 1150

Publisher

Tech Science Press

Event

Edition / version

Methods

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Geographic location

Date collected

Date created

Subject

Isogeometric analysis; Isogeometric collocation; Nearly-incompressible elasticity

Organisational unit

09697 - De Lorenzis, Laura / De Lorenzis, Laura check_circle

Notes

Funding

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