Application of streamtube techniques to full-field waterflood simulation

A comparison between streamtube and finite-difference (FD) modeling for waterfloods is presented to show the utility of streamtubes as a reservoir modeling technique. The streamtube formulation follows most of the classic techniques presented in the literature. Areal sweep in the model is determined by streamlines developed on the basis of unit mobility ratio and corrected for changing mobility ratio by the method of Martin and Wegner.(1) Displacement along the streamtubes is calculated by a Welge(2) construction with vertical heterogeneity represented by Dykstra-Parsons(3) (DP) layering. This work differs from previous efforts because wells are individually history matched by assignment of DP coefficients on a well-by-well basis. Suggestions are made for the further application of the saturation distribution resulting from the model. Two applications of the technique are described. The first is a comparison between FD and streamtube modeling for a waterflood based on the Ninth SPE Comparative Solution Project.(4) This application is designed to describe the basis of the streamtube technique in the context of a standardized industry problem. The second application is for a study of the Kaybob North reservoir that shows model development and history matching for a 100 + -well field with a 30-year history and a number of realignments.