Application of an Efficient Multiscale Finite Volume Simulatorto Practical Reservoir Models

摘要

A reservoir simulator was developed for accurate modelingrnof multiphase flow and transport in large scale heterogeneousrnreservoirs. The simulator is based on a multiscale finite volumern(MSFV) method. In MSFV, the pressure equation is solved onrncoarse grid, where coarse scale transmissibilities are computedrnvia dual basis functions (i.e., localized interpolators). The finernscale pressure and velocity field is computed as a superpositionrnof basis functions using the coarse pressure information. Thesernreconstructed properties are very accurate when comparedrnresults from a conventional fine grid simulation. In the secondrnstep, a localized and adaptive transport scheme is employedrnupdate the saturation distribution. Both IMPES and sequentiallyrnimplicit formulations are described. To resolve the finernscale flow field around wells, a special well basis functionrndevised. The multiscale algorithm is also extended to includerngravity, capillary pressure and compressibility.rnThe multiscale simulator achieves the robustness and computationalrnefficiency through scalable (efficient for large problems)rnadaptive computation of flow and transport. We establishrnthe accuracy of MSFV relative to conventional methods withrnseveral test examples. The multiscale simulator is subsequentlyrnapplied to large field scale reservoir models to demonstraternpractical use and efficiency, compared with the conventionalrnnite difference simulator.