Coupled Reservoir Geomechanical Simulations for the SAGD Process

摘要

Conventional reservoir simulation may not fully characterize the recovery mechanism of the SAGD process in uncemented oil sands reservoirs. Uncemented oil sands exhibit significantly different geomechanical behaviour from that of their cemented counterpart. Therefore, to fully explore the SAGD recovery process, coupled reservoir geomechanical simulations are required. This simulation technique can characterize both the multiphase fluid flow and reservoir parameter variations based on certain stress-strain relationships of oil sands in the SAGD process. In this paper, sequentially coupled reservoir geomechanical simulations are conducted. It is based on both the reservoir simulator, EXOTHERM, developed by T.T. & Associates Inc. and the geotechnical simulator, FLAC, developed by Itasca Consulting Group Inc. This paper discusses the strategies and methodology of the coupled reservoir geomechanical simulations for the SAGD process based on these two simulators. Meanwhile, the results of the conventional reservoir simulations and the coupled reservoir geomechanical simulations are compared. These comparisons are conducted based on initial stress conditions of K_0 = 1.0. The simulation results show that differences exist between coupled reservoir geomechanical simulations and conventional reservoir simulations under certain SAGD operation conditions.