This paper is the first part of a work that deals with the role of reservoir geomechanics in the assessment of the well's casing behavior. Evaluation of multiscale problems requires efforts of joining robust fluid-mechanical techniques with a smart global-local modeling approach. This paper presents a fluid-mechanical coupling methodology developed to evaluate the global model, in reservoir scale, employing difference and finite element methods. In order to transfer the geomechanical effects from reservoir to well scale, a multi-scale management program was also developed, following a reasonable multi-scale workflow. Theoretical aspects of these developments are presented in this paper, and applications can be found in the part II of this work.
The depletion of hydrocarbon reservoirs causes significant effects on its surroundings; the variation of pore-pressure, arising from production or injection activities, results in stress changes in the rocks that compose the field. From the geomechanical point of view, the problematic of wells and reservoirs is often distinctly addressed, mainly because the scale difference. Although the system behaves in an integrated way, the association of the phenomena involved in the analysis of wells and reservoirs is frequently neglected. In the numerical approach of multi-scale problems, it is important to investigate the best way to represent each phenomenon, and it is necessary to establish an information transfer method among the problems.
In global scale, reservoir modeling can be assessed employing fluid-mechanical coupling schemes, in order to include in the results spectrum some geomechanical aspects. Reservoir geomechanics is a subject of recent interest, and several authors have publishing different ways of perform fluid-mechanical coupling [1, 2, 3, 4, 5, 6, 7, 8]. As noted, great research effort has been devoted to the coherent consideration of geomechanical effects in the flow simulator.