Synthetic benchmark for the computation of equivalent properties in coupled flow and geomechanics conditions for a fractured carbonate rock

• Autor(a) principal: Falcão, F.
• Data de Publicação: 2018
• Outros Autores: Barroso, J., Murad, M., Pereira, P., Vargas, E., Juvinao, A., Muller, A., Roehl, D., Quevedo, R., Mejia, C., Guimarães, L., Beserra, L., Alvarez, L., Cleto, P. [UNESP], Manzoli, O. [UNESP]
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/221231

In this work, we report on a successful benchmark program motivated by the development of robust hydro-mechanical coupled models capable of providing accurate equivalent properties, such as permeability and porosity, in larger computational cells, typical of an outcrop scale. The cells are occupied by a poroelastic fractured carbonate rock. Different research groups were invited to propose models and discretizations for the benchmark problem considering some basic premises. The construction of fine-scale models revolves around the non-linear elastic constitutive law postulated by Barton and Bandis between normal stress and normal displacement behavior. The local non-linear coupled poroelastic (matrix) - nonlinear elastic (joints) - flow (single phase) problem is solved under oedometric conditions considering a single realization of fractures locations generated through geostatistical analysis. The different research groups used a variety of techniques to solve the complex fine-scale problem. Among these techniques we may highlight embedded fracture elements [1], solid finite elements with high aspect ratio [2], augmented Lagrangian formulation [3, 4], local refinement with jump components [5] and zero thickness interface elements [6]. Numerical simulations show the magnitude of the equivalent permeabilities and local profiles, such as displacement jumps, as a function of the stress state, characterized by the pore pressure and overburden stresss. Finally, we present comparisons between the outcomes of each technique.