The use of reservoir simulation coupled with geomechanics to model physical phenomena such as compaction, subsidence, induced fracturing, enhancement of natural fractures and/or fault activation, SAGD recovery etc.., has been increasing. Among different methods investigated by researchers. The iterative explicit method appears to be the preferred method for field-scale simulation. This method is a loose coupled approach between a reservoir and a geomechanical simulator. At user-defined steps, the fluid pressures are transmitted to the geomechanical tool which computes the actual stresses and reports the modifications of porosities and permeabilities back to the reservoir simulator. In the classical iterative scheme, at each stress equilibration step, the reservoir simulation needs to be restarted from the previous converged step. This scheme can be difficult to implement within an industrial IT environment. This paper presents a new iterative scheme which allows: - any reservoir simulator, - to be coupled with any nonlinear FEM package for the stress analysis without any limitation on the functionality of either simulator. The convergence of this new scheme is discussed and results are presented for three cases described below. The first case is a validation case used by other SPE papers. The second case is a synthetic model of a highly compacting reservoir sensitive to water saturation. The third one is a full field reservoir model. Faults are modeled inside the reservoir CPG grid and also inside the geomechanical mesh using specific cohesive elements. In all cases, convergence is achieved in a few iterations and results are comparable to those obtained with previously tested methods. The feasibility of the proposed coupling approach using industrial software is proved. Another advantage compared to the standard iterative scheme is the ability to compare production profiles over the complete time history at the end of each geomechanical iteration. The reservoir engineer evaluates the coupling effects and ends the iterative process when production curves variations between two iterations are no longer significant.
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