Development of an In-house Two-dimensional Streamline Simulator and its Comparison with a Commercial Simulation Software

Predicting the reservoirs’ future performance is of great importance especially to the managersand operators of the field due to the political and economic considerations. To this end, thereservoir simulators are used by the engineers to numerically solve the pressure and saturationequations emerging from some mathematical PDEs (Partial Differential Equations). Mostreservoir simulators employ a well-known FD (Finite Difference) discretization scheme to comeup with the matrix of the unknowns at the porous medium.However, solving for the dependent variables at the three dimensional medium requires hugecomputational time and fine gridding to capture the physical complexity of the problem. Hence,SLS (Streamline Simulation) has been proposed for this purpose to decouple the saturationequation from the actual 3D medium, solving the saturations along the streamlines which areoriginated from production to the injection wells and tracked by the velocity field, and thensending back the saturation information to the actual 3D medium. The two main steps in SLS aredescribed graphically in Fig. 1. Also, as it is depicted in Fig. 2, SLS is more advantageous incomparison with FD simulation when model size is very large while complexity of the physicalflow mechanism is not much (Datta-Gupta and King, 2007).