Preprint C37/2005
Perda de Injetividade em Reservatórios Estratificados
Julia Wrobel
Keywords: perda de injetividade | meios porosos | computação científica
This study is motivated by the production of oil throug the injection of water in stratified porous media. The injected water is not pure - it contains oil drops, bacteria and chemical elements, each one with its own capability to reduce the permeability in the neighborhood of the well. The main goal of this work is to develop a computational tool that allows the study and, in the future, the validation of models proposed in the literature and of their respective particle retention mechanisms. Within this context, we intend to provide computational evidence that the numerical model captures different trajectory patterns. These patterns depend on whether we have particle retention or not and, consequently, if particle migration occurs between layers. To do so, we apply a mechanic formulation for the flux of water containing suspension particles. At the present time we do not consider any chemical or thermodynamical interaction between fluid and reservoir. The three dimension mathematical model considers a cylindrical axissymmetric geometry. We study the evolution of the concentration of suspended and deposited particles in a heterogeneous, vertically stratified reservoir. In particular, we test empirical retention models, the way the particles are retained in the medium and its consequences. The numerical tools used in this study are the method of characteristics for the transport and deposition of particles, coupled with the finite element method (lowest order Raviart-Thomas) for the velocity and pressure.