Coupled Well Card Options (CO2E)

The coupled well model for STOMP-CO2e allows the specification of both injection and production type wells.  Injection wells are mass type and production wells can be either volumetric or mass type wells.

Well Trajectories

Well trajectories are specified using straight-line segments, in the natural drilling direction.  The individual well sections can be screened or unscreened and have associated radii and skin factors.  The trajectories of  well sections are specified via a starting (i.e., first transition point) x, y, z point in the global coordinate system and an ending (i.e., second transition point) x, y, z point in the global coordinate system.  Well trajectories are not permitted that coincide with a grid-cell surface.  The only portions of the well trajectories that are active are those within a grid-cell volume. The translation of well trajectories into well nodes and connections between well nodes and field nodes will require computational time at the start of the simulation.  For large domains and large well counts this initialization stage will require some time to complete, but is only required at the start of the simulation.

Aqueous or CO₂ Injection Wells

The injection well is used to specify the injection of a fluid at a particular mass rate.  Fluid will be injected from the well into the field grid cells across the screened interval.  The distribution of fluid crossing the well surface depends on the resistance to flow as defined by the local well index, fluid mobility, and driving force across the well surface.  The fluid injection rate is additionally bound by a pressure limit at the top of the screened interval; where the screened interval is assumed to be located at the point where the well trajectory crosses into the computational domain.  Injection mass wells can be time varying. The injection schedule is divided into time periods and time points. The thermodynamic state of the fluid can only vary between time periods. For aqueous injections, dissolved CO₂ and dissolved salt injection options are available.

Production Well (Volumetric or Mass)

The production well is used to specify the production of all fluids (i.e., aqueous and gas) from the screened intervals of the well.  Fluids enter the well based on the resistance to flow as defined by the local well index, fluid mobility, and driving force across the well.  Fluids are not permitted to flow from the production well into the field domain.  Pressure within the production well is based on the specified pressure at the bottom, in reference to the natural drilling direction, screened interval of the well, and the local density of the produced fluids.  Local liquid density is computed as an average of the locally produced fluids.