A streamline simulation method for heterogeneous oil reservoirs considering permeability tensor

Key words:  reservoir  anisotropy  permeability tensor  streamline model  numerical simulation

Abstract:

Considering the anisotropic permeability in oil reservoirs, a streamline simulation method with full permeability tensor was established. A nineteen-point finite-difference scheme was used in pressure equation to calculate the pressure distribution. The velocity profile was calculated by Darcy 's law with full permeability tensor, and the streamline was traced by Pollock method. The oil saturation at every point on each streamline was calculated based on one dimensional water displacement theory. The calculated results for reservoirs with different permeability tensor show that pressure propagates faster along the direction of maximum principal permeability. The orientation of the streamlines and the direction of pressure gradient are generally inconsistent due to the introduction of a cross term during the velocity calculation. If injector and producer are placed perpendicular to the direction of maximum principal permeability, it can make the streamline distribution more evenly throughout the reservoir, which can improve the efficiency of water flooding.