Modeling the behavior of CO₂ injection in a sand reservoir

Injection CO₂ into subsurface formation changes in-situ pore pressure and temperature which in turn alters the effective stress condition. An attempt to analyze the geomechanical responses induced by CO₂ fluid injection in a sand reservoir is performed on this study. The objective of this study is to develop Graphical User Interface (GUI) of coupling program code that linking two existing and proven programs, TOUGH2 and FLAC3D, for coupled fluid flow – geomechanics modeling. TOUGH2 is a numerical simulator that solves fluid-flow and transport equation, whilst FLAC3D is a numerical code to simulate geomechanical analysis. Fluid – flow and geomechanical equations are sequentially solved by using finite difference methods. The coupling method used in this paper is two – way coupling where the coupling parameters are transferred from each code in certain time step. The simulation is conducted to know the reservoir behavior geomechanically. The pore pressure, stress alteration and displacement induced by CO₂ fluid injection is shown and be analysed. This model could be applied to other field and serve as a basis information for the injection strategy.