PVTGW
Recognised by the OPM Flow parserPROPS
PVTGW defines the gas PVT properties for dry gas1 Natural gas that occurs in the absence of condensate or liquid hydrocarbons, or gas that had condensable hydrocarbons removed, is called dry gas. It is primarily methane with some intermediates. The hydrocarbon mixture is solely gas in the reservoir and there is no liquid (condensate surface liquid) formed either in the reservoir or at surface. The term dry indicates that the gas does not contain heavier hydrocarbons to form liquids at the surface conditions. Dry gas typically has GOR's greater than 100,000 scf/stb or 18,000 Sm3/m3. with vaporized water. This keyword should be used when the VAPWAT keyword has been declared in the RUNSPEC section indicating that vaporized water is present in the dry gas phase. The keyword may be used for gas-water and oil-water-gas input decks that contain the dry gas and vaporized water phases.
Natural gas that occurs in the absence of condensate or liquid hydrocarbons, or gas that had condensable hydrocarbons removed, is called dry gas. It is primarily methane with some intermediates. The hydrocarbon mixture is solely gas in the reservoir and there is no liquid (condensate surface liquid) formed either in the reservoir or at surface. The term dry indicates that the gas does not contain heavier hydrocarbons to form liquids at the surface conditions. Dry gas typically has GOR's greater than 100,000 scf/stb or 18,000 Sm3/m3.
Note
This is an OPM Flow specific keyword for the simulator’s Water Vaporization Model that is activated by declaring that vaporized water is present in the run.
Notes:
The keyword is followed by NTPVT tables as declared on the TABDIMS keyword in the RUNSPEC section.
Each table must contain a minimum of two rows and a maximum of NPPVT rows and NRPVT Rw entries as declared on the TABDIMS keyword in the RUNSPEC section.
Apart from the PRES data there must be same number of entries for each column.
Each sub table defining the under saturated gas properties must be terminated by “/”.
Each main table is terminated by a single “/” on a separate line and there is no “/” terminator for the keyword.
Note that provided the first table has been entered, subsequent tables may be defaulted, in this case the prior table is copied to the current table.
Note
If both the VAPWAT and VAPOIL keywords have been declared in the RUNSPEC section indicating that both vaporized water and vaporized oil are present in the wet gas, then the PVTGW keyword should be used along with the PVTG keyword in the PROPS section to fully define the wet gas PVT properties. The PVTGW keyword should be used to define the gas properties as a function of pressure and water-gas ratio (RVW), assuming oil-saturated gas. The PVTG keyword should be used to define the gas properties as a function of pressure and oil-gas ratio (RV), assuming water-saturated gas.
Alternatively, the PVTGWO keyword in the PROPS section may be used instead of the PVTGW and PVTG keywords to fully define the wet gas PVT properties.
See also the PVTG keyword in the PROPS section that defines the wet gas PVT for when vaporized oil is present in the gas phase. Alternatively, the PVTGWO keyword in the PROPS section may be utilized instead of PVTG and PVTGW to fully define the wet gas PVT properties, for when both vaporized oil and water are present in the gas phase.
- Records
- One or more records, each terminated by
/ - Variadic
- The record accepts a variable number of items
Parameters
| No. | Name | Description | Type | Dimension | Field | Metric | Lab | Default |
|---|---|---|---|---|---|---|---|---|
| 1 | GAS_manual: PRESS | A real monotonically increasing down the column vector that defines the gas phase pressure, associated with the corresponding saturated water-gas ratio (“WGR”) or Rw, the gas formation volume factor, and the gas viscosity for the stated saturated RWS. For a given PRESS the variability of the gas formation volume factor and the gas viscosity with respect to the under-saturated Rw is optionally included as a sub table under RWU, FVFU and VISU columns, that is it is not necessary to repeat PRESS for each sub table entry. However, each sub table must be terminated by a “/”. The under saturated Rw entries are optional, except for perhaps the last PRESS entry to define the PVT properties above the initial saturation pressure. | DOUBLE | Pressure | psia | barsa | atma | None |
| 2 | DATAmanual: RWS / | A columnar vector of real positive numbers for both the saturated (RWS) and under saturated (RWU) Rw sub table entries. The RWS entry on the main table is the saturated WGR at the pressure indicated by PRESS and may be increasing or decreasing in value as PRESS varies. Subsequent under-saturated Rw for a sub table at the given PRESS, as defined by RWU, are monotonically decreasing for entries in a given sub table. | DOUBLE | OilDissolutionFactor, OilDissolutionFactor, Viscosity | stb/ | sm3/ | scc/ | None |
| 3 | FVFS / | A columnar vector of real decreasing down the column values that defines the corresponding gas phase formation volume factor for a given pressure (PRESS) and for a given Rw (either RWS or RWU). | rb/ | rm3/ | rcc/ | None | ||
| 4 | VISS / | VISS a columnar vector of real increasing down the column values that defines the corresponding gas phase viscosity for a given pressure (PRESS) and for a given RWS. VISU a columnar vector of real decreasing from VISS down the column values that defines the corresponding gas phase viscosity for a given pressure (PRESS) and for a given RWU. | cP | cP | cP | None |
Example
--
-- GAS PVT TABLE FOR DRY GAS WITH VAPORIZED WATER (OPM FLOW KEYWORD)
--
PVTGW
-- PRES RW BG VISC
-- PSIA SM^3/SM^3 RM^3/SM^3 CPOISE
-- ------ --------- ------- ------
300 0.000479 0.042340 0.01344
0 0.042310 0.01389 /
600 0.000469 0.020460 0.01420
0 0.020430 0.01450 /
900 0.000403 0.013280 0.01526
0 0.013250 0.01532 /
1200 0.000354 0.009770 0.01660
0 0.009730 0.01634 /
1500 0.000272 0.007730 0.01818
0 0.007690 0.01752 /
1800 0.000225 0.006426 0.01994
0 0.006405 0.01883 /
2100 0.000191 0.005541 0.02181
0 0.005553 0.02021 /
2400 0.000163 0.004919 0.02370
0 0.004952 0.02163 /
/ TABLE NO. 1
-- PRES RW BG VISC
-- PSIA SM^3/SM^3 RM^3/SM^3 CPOISE
-- ------ --------- ------- ------
300 0.000479 0.042340 0.01344 /
600 0.000469 0.020460 0.01420 /
900 0.000403 0.013280 0.01526 /
1200 0.000354 0.009770 0.01660 /
1500 0.000272 0.007730 0.01818 /
1800 0.000225 0.006426 0.01994 /
2100 0.000191 0.005541 0.02181 /
2400 0.000163 0.004919 0.02370 /
/ TABLE NO. 2
The above example defines two dry gas PVT tables assuming NTPVT equals two and NPPVT is greater than or equal to eight on the TABDIMS keyword in the RUNSPEC section.
Notice that there is no terminating “/” for this keyword only for a table and a sub table.
| Note This is an OPM Flow specific keyword for the simulator’s Water Vaporization Model that is activated by declaring that vaporized water is present in the run. |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Note If both the VAPWAT and VAPOIL keywords have been declared in the RUNSPEC section indicating that both vaporized water and vaporized oil are present in the wet gas, then the PVTGW keyword should be used along with the PVTG keyword in the PROPS section to fully define the wet gas PVT properties. The PVTGW keyword should be used to define the gas properties as a function of pressure and water-gas ratio (RVW), assuming oil-saturated gas. The PVTG keyword should be used to define the gas properties as a function of pressure and oil-gas ratio (RV), assuming water-saturated gas. Alternatively, the PVTGWO keyword in the PROPS section may be used instead of the PVTGW and PVTG keywords to fully define the wet gas PVT properties. |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|Manual source: parts/chapters/subsections/8.3/PVTGW.fodt