Abstract
During the late 1990's, Exxon and Mobil had each independently developed next-generation reservoir simulation systems. Both next-generation systems embodied a substantial number of step-out simulation technologies, which were extremely complementary. ExxonMobil moved aggressively to combine the best of both companies' technologies into one industry-leading simulation system called EMpower™. This new simulation system is currently being used to actively manage ExxonMobil's global resource base. Key features of this industry-leading simulator are described in this paper.
The new simulator employs unstructured grids to more accurately model complex geologic features, near-wellbore flow, and aquifer support. The computations are performed within the unstructured grid fabric. Interactive simulation ties together the geologic and reservoir simulation models with production data yielding high-confidence forecasts of future performance.
The linear systems that are created by an unstructured grid cannot be efficiently solved by conventional solution methods normally applied to simulators using rectilinear gridding. As a result, ExxonMobil looked to collaborate on research and development activities in the area of linear solvers for unstructured grids area and found capable research and development peers in Russia. The technical capabilities of the Russian scientific community were a natural fit to help develop a new library of linear solution methods geared towards the matrices created by the EMpower unstructured simulator. This collaborative effort yielded an unstructured linear solution library called SparSol and is the result of over 20 work years of effort at four Russian research organizations and contains numerous methods for efficiently solving the unstructured matrices produced by the EMpower unstructured reservoir simulator.
