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An adaptive finite element model for wellbore breakout simulation |
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| Authors: | Diogo L Cecílio Philippe R B Devloo Sônia M Gomes Erick SR Santos |
| Institution: | 1. Escola de Engenharia de São Carlos, Universidade de São Paulo, Brazil;2. Faculdade de Engenharia Civil, Universidade Estadual de Campinas, Brazil
Instituto de Matemática, Estatística e Computação Científica, Universidade Estadual de Campinas, Brazil;3. Instituto de Matemática, Estatística e Computação Científica, Universidade Estadual de Campinas, Brazil;4. Centro de Pesquisas Leopoldo Américo Miguez de Mello, Petrobras, Rio de Janeiro, Brazil |
| Abstract: | A finite element formulation is proposed and implemented for analysing the stability of excavated wells using the DiMaggio-Sandler constitutive elastoplastic model with a typical carbonate reservoir configuration. The quality of the finite element approximation is ensured by applying smooth curved elements adapted to the wellbore geometry, and h ? p adaptive finite element meshes in the plastic zone. General purpose procedures are defined to transfer the elastoplastic deformation history to newly created integration points. A breakout damage criterion is proposed based on the second invariant of the deviatoric plastic deformation tensor. This damage criterion is used to apply a mesh movement algorithm to represent material collapse. The automatic successive application of the breakout damage criterion results in elliptical realistically looking geometries obtained in experiments reported in the literature. |
| Keywords: | finite elements geomechanics mesh adaptation plasticity return-mapping algorithm wellbore stability |