Rubis workflow
The grid is built automatically as a final step after the
physical problem has been defined by the input of
the PVT, the geometry, the wells and the reservoir
static properties.
Defining the PVT
The numerical solver is compositional, however
the PVT used is black-oil or modified black-oil. The
Rs and rs relations are turned into a composition
ratio, providing the grounds for a compositional
formulation. Internal correlations can be used and
tuned to match measured values. Alternatively,
tables can be loaded.
Defining the reservoir geometry
The user defines the areal perimeter of the reservoir
and the number of geological layers. Individual
layer volumes are defined by drawing or importing
horizons and thickness fields. Internal faults can be
defined. Scarce information is compensated for by
kriging or linear interpolation. Vertical cross-sections
can be created and viewed.
Defining the reservoir properties
Reservoir properties that include petrophysical,
relative permeability, capillary tables and fluid
contacts may be defined by layer or areas or a
combination of both. In addition, non-Darcy flow,
double-porosity, vertical and horizontal anisotropy
may be specified. Each segment of the reservoir
boundary can be set individually to sealing, constant
pressure, or connected to various types of aquifers.
Importing geometry and properties
The interactive build may be replaced by an import
from a geomodeler or another simulator using
GRDECL or CMG format including the net-to-gross.
It is also possible to drag-drop a case, or part of a
case, from another Rubis document or from a Saphir
or Topaze numerical model.
Defining the well geometry
A well in Rubis may be either vertical, vertical with
a hydraulic fracture, horizontal or slanted. The
‘
wriggly well’ can follow any trajectory and cross
any stratigraphy. Perforations are unlimited with
opening and closing times defined individually.
Each perforation may have a discrete skin which
may be constant, rate or time dependent. Because
a wellbore model can be coupled with options
including classical empirical, mechanistic and drift
flux models, the well definition is not limited to its
actual path in the reservoir. It is therefore possible to
define the complete well trajectory from surface.
Using an Amethyste wellbore model in Rubis
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