New Methodology for Numerical Simulation of Water-Alternating-Gas (WAG) Injection
H.A. Alzayer, A. Jahanbakhsh and M. Sohrabi
Event name: IOR 2017 - 19th European Symposium on Improved Oil Recovery
Session: Miscible/Immiscible Gas Injection
Publication date: 24 April 2017
Info: Extended abstract, PDF ( 1.47Mb )
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A new methodology is presented to simulate WAG injection scenarios. In addition to properly model three-phase flow, the concept of directional and cyclic hysteresis is modelled to capture the underlying physics. Laboratory measured data is used to validate the proposed methodology. The approach in this paper is based on updating parameters of WAG hysteresis model during the course of cyclic injection to adequately model the key physical mechanisms in WAG injection tests. For this study, we used ‘Modified Stone 1’ model for calculating three-phase relative permeability (kr) data from measured two-phase kr. We used Land’s parameter (C) and the reduction exponent (alpha) for gas secondary drainage relative permeability as the variable parameters in WAG hysteresis model for matching the coreflood production and pressure data. Results of this study showed that, by applying the proposed methodology for simulating WAG coreflood experiments at different wettability conditions, better match to the experimental data can be achieved. In this paper, we highlight the shortcomings of the current capability of numerical simulators for simulating WAG injection. Some areas of improvement to the current WAG hysteresis model is introduced and a new methodology is proposed to improve the performance of current simulation procedures for WAG injection scenarios.