Coarse Grid Generation Based on Vorticity for Reservoir Flow Simulation: Extension to Unstructured Grid

One of the key inputs to the reservoir simulator is the simulation model generated from fine grid geological models of reservoir. Constructing an appropriate simulation model which represents static and dynamic behavior of reservoir is one of the active research areas in reservoir engineering. In this paper, we present a new version of vorticity-based gridding technique applicable to complex and highly heterogeneous reservoir where structured Cartesian grids fail to capture details of model. In the technique, single phase flow is performed on the original fine grid geological model, and then vorticity is calculated from velocity field. Obtained vorticity map is used to adjust the boundaries of the grid cells, in such a way that areas of larger vorticity are kept fine and low vorticity regions are coarsened. Use of unstructured grid helps block boundaries to better conform to the complicated features (compared to structured Cartesian grid), and reduce the grid orientation effects. Our two-phase simulation results demonstrate that unstructured vorticity-based gridding perform much closer to the fine grid than uniform gridding.

کلیدواژه ها:

Vorticity ، Coarse Grid ، Unstructured Grid ، Simulation ، Upscaling