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arXiv · 1706.01275

On Mixed Isogeometric Analysis of Poroelasticity

Yared W. Bekele·Eivind Fonn·Trond Kvamsdal·Arne M. Kvarving·Steinar Nordal
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Abstract

Pressure oscillations at small time steps have been known to be an issue in poroelasticity simulations. A review of proposed approaches to overcome this problem is presented. Critical time steps are specified to alleviate this in finite element analyses. We present a mixed isogeometric formulation here with a view to assessing the results at very small time steps. Numerical studies are performed on Terzaghi's problem and consolidation of a layered porous medium with a very low permeability layer for varying polynomial degrees, continuities across knot spans and spatial discretizations. Comparisons are made with equal order simulations.

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Yared W. Bekele, Eivind Fonn, Trond Kvamsdal, Arne M. Kvarving, Steinar Nordal. 2017-06-05. On Mixed Isogeometric Analysis of Poroelasticity. https://doi.org/10.3390/app12062915

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