Coarse scale simulation of horizontal wells in heterogeneous reservoirs

An upscaling approach appropriate for the generation of coarse scale simulation models of horizontal wells is developed and applied. The method entails the solution of a general, single-phase, well-driven flow problem over a limited fine scale domain. Coarse scale simulation parameters (transmissibilities and well indexes) are computed from this solution using either an averaging procedure or, to achieve higher degrees of accuracy, an optimization procedure. The method is applied to single- and three-phase flow problems in several different heterogeneous permeability fields. Global coarse scale simulation results using the near-well upscaling procedure are shown to be in consistently close agreement with the reference fine grid simulation results. Results using standard coarse scale models (with no near-well upscaling) are shown to be in considerable error in many cases. The overall upscaling method can be generalized to more complex, deviated and multilateral well configurations.