Eclipse Input Data
Eclipse Input Data is collected in an input data file, which is an ordinary text file. However, in some cases, the geometry of the grid can be set in the binary format.
All data is described according to Eclipse Syntax and divided into sections. Some of sections are optional.
RUNSPEC
This section is required.
Run specifications. Includes a description of the run, such as grid size, table sizes, number of wells, which phases to include an so forth.
Example:
RUNSPEC -- section header OIL -- keyword without data WATER DIMENS -- keyword with data 24 25 15 / -- data associated to keyword DIMENS
GRID
This section is required.
Defines the grid dimensions and shape, including petrophysics (porosity, permeability, net-to-gross).
There are 2 formats of ECLIPSE grid: ASCII (*.GRDECL) and BINARY(*.GRID, *.EGRID) formats. (see how to convert them)
ECLIPSE Grid ASCII format
ECLIPSE Grid ASCII format is treated as other model properties, according to Eclipse Syntax.
To describe Grid in ASCII format the following set of keywords may be used:
TOPS - Depth of the top face of each grid block
DX - Block size along direction X
DY - Block size along direction Y
DZ - Block size along direction Z
for example:
DX 300*1000 / DY 300*1000 / DZ 300*50 / TOPS 100*5000 100*5050 100*5100 /
or
COORD - Coordinate lines
ZCORN - Depths of grid block corners
for example:
COORD 0 804.529166 1111.662354 0 804.529166 1176.043701 12.329783 782.714932 1111.65564 12.329783 782.714932 1176.118774 24.649314 760.902612 1111.680298 ... 451.113147 1133.56604 1237.177243 451.113147 1196.893433 / ZCORN 1111.662354 2*1111.65564 2*1111.680298 2*1111.756836 2*1111.877441 2*1112.050171 2*1112.270508 2*1112.539429 2*1112.816528 2*1113.097168 2*1113.406006 2*1113.716431 ... 2*1196.927368 1196.893433 /
Exported from Petrel model use COORD + ZCORN.
Usually GRID data is too large to keep in .DATA file, it's often allocated in separate file.
To do this INCLUDE keyword is used:
-- section GRID INCLUDE 'MODEL.INC' /
ECLIPSE Grid Binary Format
ECLIPSE BINARY GRID (".GRID" or ".EGRID" - extensible grid) is a detached Binary file, it cannot be read by Notepad or other text editor.
To use binary grid GDFILE keyword is used:
-- section GRID GDFILE MODEL.GRID /
EDIT
This section is optional.
This section is used to define changes to the grid data. For example manual edit of porosity or permebility.
PROPS
This section is required.
In this section fluid and rock properties (relative permeabilities, PVT tables, ...) are defined.
REGIONS
This section is optional.
The REGIONS section divides the grid into regions. The common regions are:
- SATNUM Saturation table regions (relative permeability and capillary pressure)
- EQLNUM Equilibration regions (setting initial pressures and saturations).
- PVTNUM PVT data regions (fluid densities, FVFs, viscosities).
- FIPNUM Fluid-in-Place regions.
If there is no REGIONS section, ECLIPSE puts all grid blocks into a single region for all the
above operations.
SOLUTION
This section is required.
In the SOLUTION section the initial state (pressure, saturations, compositions) is defined.
SUMMARY
This section is optional.
The SUMMARY section is used to define output data. A number of variables (e.g. average field pressure, well oil production rate, well water injection etc.) that are to be written to Summary files must be spesified here.
If there is no SUMMARY section, ECLIPSE does not create any Summary files.
SCHEDULE
This section is required.
Section SCHEDULE used for well definitions, description of operating schedule, convergence control.
Data Input Example
To run this model create text file, copy the content below, name this file with ".DATA" extension and run it with ECLIPSE.
RUNSPEC
-- Title is used as header on output, to identify run
TITLE
Example Simulation
-- Specify dimension of model, NX, NY, NZ
DIMENS
-- NX NY NZ
10 10 3 /
-- Phases included (oil and water, i.e. 2-phase run)
OIL
WATER
-- Units to use, METRIC, FIELD or LAB
FIELD
-- Specify maximum values for well data
WELLDIMS
-- max.wells; max.cell-connections; Next three values are defaulted
4 5 3* /
-- Start date, i.e. “Day 0” in simulation
START
1 'JAN' 2012 /
GRID
-- Definition of grid cells. From DIMENS keyword above, we have:
-- N = NX*NY*NZ = 10*3*3 = 90.
-- In each cell DX = DY = 1000 ft and DZ = 50 ft
-- (Dimension measured in feet since units were defined as FIELD above)
-- The grid cells are then defined by:
DX
300*1000 /
DY
300*1000 /
DZ
300*50 /
--depths which are consistent with the DZ-values defined by:
TOPS
100*5000 100*5050 100*5100 /
-- Permeabilities are constant, so define 300 equal values.
PERMX
300*100 /
PERMY
300*100 /
PERMZ
300*20 /
-- Porosity is constant in each layer, so define 100 values in layer 1, 100 in layer 2, and 100 in layer 3.
PORO
100*0.3
100*0.23
100*0.18 /
PROPS
-- Relative permeability for water and oil,
-- and water-oil capillary pressure, as a function of water saturation
SWOF
-- Sw Krw Krow Pcow
0.2 0.00 1.00 326.2
0.3 0.01 0.99 168.7
0.4 0.02 0.88 101.2
0.5 0.03 0.67 67.4
0.6 0.04 0.56 52.9
0.7 0.06 0.39 42.4
0.8 0.19 0.16 0.00
0.9 0.45 0.00 0.00
1.0 0.78 0.00 0.00
/
-- PVT properties for water.
-- Pref: Reference pressure for rest of data (psi)
-- Bw: Volume formation factor for water
-- Cw: Water compressibiblity
-- ViscW: Water viscosity
PVTW
-- Pref Bw Cw ViscW
4014.7 1.029 3.13D-6 0.31 0 /
-- PVT properties for oil
PVDO
-- P Bo viscO
3337.0 1.2600 1.042
3725.0 1.2555 1.072
4139.5 1.2507 1.096
4573.2 1.2463 1.118
5053.9 1.2417 1.151
5487.5 1.2377 1.174
5813.9 1.2356 1.2 /
-- Dead oil: Rs (Gas resolution factor) is constant
RSCONST
-- Rs Bubble-point-pressure
0.4 3337.0 /
-- Specify constant rock compressibility.
ROCK
-- Pref Cr
14.7 3.0D-6 /
-- Fluid densities at surface conditions
DENSITY
-- Oil Water Gas
49.1 64.79 0.06054 /
SOLUTION
EQUIL
-- DD = Datum depth, the depth to which all reports will be referenced.
-- DD Pres.at.DD OWC Pcow(OWC) Default rest of data items
5000 4800 6000 0.0 6* /
SUMMARY
-- List data vectors which we want stored for graphics post-processing
-- Field Oil Production Rate
FOPR
-- Field Oil Production Total
FOPT
-- Field Pressure (averaged reservoir pressure)
FPR
-- Field Oil In Place
FOIP
-- Field Water Production Rate
WWPR
-- Field Water Injection Rate
WWIR
-- Well Water Cut for all wells
WWCT
/
SCHEDULE
-- Specify output of graphics result files for cell data, and times which to write these.
RPTRST
BASIC=5 NORST=1 FREQ=6 /
-- Well specification: Give names, positions (i, j) and main phase of wells
WELSPECS
--wname group i j Z(bhp) prefPhase
'WP1' 'G' 10 2 1* 'OIL' /
/
-- Completion data, the well is open to the reservoir in cells in layers from k_hi to k_lo.
COMPDAT
--wname ic jc k_hi k_lo open/shut 2*default well_diam 4*default
'WP1' 10 2 1 2 'OPEN' 2* 0.5 4* /
/
-- Well WP1 will produce with an oil rate of 2000 STB/day constrained by that well’s flowing bottomhole pressure is minimum 3350 psi.
WCONPROD
--wname open/shut ctrlmode orat 4*Default bhpmin Rest default
'WP1' 'OPEN' 'ORAT' 2000 4* 3350 /
/
-- Milestone dates, e.g. to write results
DATES
1 'FEB' 2012 /
1 'MAR' 2012 /
/
-- Change production rate to 4000 STB/day
WCONPROD
--wname open/shut ctrlmode orat 4*Default bhpmin Rest default
'WP1' 'OPEN' 'ORAT' 4000 4* 3350 /
/
DATES
1 'APR' 2012 /
/
DATES
1 MAY 2012 /
/
DATES
1 JUN 2012 /
/
DATES
1 JUL 2012 /
/
DATES
1 AUG 2012 /
/
DATES
1 SEP 2012 /
/
DATES
1 OCT 2012 /
/
DATES
1 NOV 2012 /
/
DATES
1 DEC 2012 /
/
DATES
1 JAN 2013 /
/
END
See also
Eclipse Syntax
ECLIPSE Dataset Example
Basics of Reservoir Simulation with the Eclipse Reservoir Simulator from Øystein Pettersen, Dept. of Mathematics, Univ. of Bergen, 2006