INTERFACE POINT METHOD MODELING OF THE STEAM-ASSISTED GRAVITY DRAINAGE PRODUCTION OF OIL

摘要

A computer system and method of simulating the behavior of an oil and gas reservoir including movement of the steam-bitumen interface during oil production using the Steam Assisted Gravity Drainage (SAGD) technique. A system of equations including state equations involving momentum and heat transport for each phase, mass conservation equations, and heat balance equations, in combination with a continuity constraint, is defined and discretized for the modeled volume. A material point model technique for numerically solving the system of discretized equations is applied, where interface marker particles that move through the Eulerian grid represent the location of points along the steam-bitumen interface.

主权项

1. A method of operating a computer system to simulate the fluid and structural behavior of a volume of the earth near a wellbore, comprising the steps of:
retrieving, from a memory resource in the computer system, parameters defining properties of a sub-surface formation in the volume to be simulated at each of a plurality of mesh nodes in a grid representative of that volume; selecting initial boundary conditions at each of the plurality of mesh nodes; then, at each of a plurality of time steps over a simulation time period, operating the computer system to perform a plurality of operations comprising:
solving a system of equations comprising one or more state equations corresponding to transport mechanism models and balance constraints at each of a plurality of interface marker particles corresponding to the location of a steam-bitumen interface within the volume;communicating values corresponding the solution of the system of equations to mesh nodes near each of the plurality of interface marker particles;evaluating macro-scale equations corresponding to fluid flow at the plurality of mesh nodes;updating the boundary conditions at the plurality of mesh nods responsive to the result of either or both of the solving and evaluating operations; andchanging the location of one or more of the interface marker particles responsive to the results of either or both of the solving and evaluating operations to estimate movement of the interface marker particles within the volume over the simulation time period.