Modelagem computacional do acoplamento hidro-geomecânico em reservatórios não-convencionais de gás

• Autor(a) principal: Volpatto, Diego Tavares
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do LNCC
• Texto Completo: https://tede.lncc.br/handle/tede/245
• topic: Reservatórios de gás; Método de elementos finitos; Algoritmos numéricos; Gas reservoir; Finite element methods; Numerical algorithms; CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::GEOLOGIA::PETROLOGIA

The present work aims at constructing a new sequential hydro-mechanical model of gas reservoirs. The new aspect of the proposed model lies on the derivation of new source terms in the subsystems of hydrodynamics and geomechanics. When compared with the fully-coupled formulation, where the two systems are solved simultaneously, the proposed formulation allows to explore the difference in the time-scales of the two phenomena. In addition the sequential formulation can be naturally extended to treat impermeable adjacent rocks and overcomes the problem of lack of stability in the impermeable regions of the geological formation. The formulation proposed based on the fixed stress split algorithm is unconditionally stable in the iterative procedure for coupling the two subsystems. This continuum problem is discretized by the Galerkin method coupled with fixed point algorithms to handle non-linearities present in the equation of state of the gas and in the coupling between the two subsystems. Numerical simulations are performed to illustrate the influence of geomechanical effects upon gas production. Comparisons between the well known one and two-way formulations are also presented.