GRUPNET
Recognised by the OPM Flow parserSCHEDULESPECIAL
I don’t think this is supported.
Reply to Atgeirr Rasmussen (09/20/2017, 13:28): "..."
But it is in the Norne model to model the surface network, will switch to orange for now.
The GRUPNET keyword defines the standard group network parameters used to model the flow and pressures behavior within the network. The group hierarchy is defined by the GRUPTREE keyword and wells are assigned to groups using the WELSPECS keyword, both keywords are in the SCHEDULE section.
Group pressure values are optionally entered for each group in the network together with a vertical flow (lift) performance (“VFP”) table that the determines the pipeline pressure behavior from the LOWER to the HIGHER group given the current flowing conditions; the group relationship is defined by the GRUPTREE keyword. The VFP table is entered via the VFPPROD keyword for production pipelines and VFPINJ for injection pipelines. These are the same keywords as used for well modeling, however, the manner in which they are generated by an external program is completely different when used for pipeline modeling.
Notes:
The keyword is followed by any number of records with each record terminated by a “/” and the keyword should be terminated by a “/”.
See also the WELSPECS keyword to define wells, the VFPPROD and VFPINJ keywords that define the vertical lift performance table to be used for calculating the pipeline pressures connecting the LOWER and HIGHER group in the network. All the aforementioned keywords are described in the SCHEDULE section.
- Records
- One or more records, each terminated by
/ - Items per record
- 7
Parameters
| No. | Name | Description | Type | Dimension | Field | Metric | Lab | Default |
|---|---|---|---|---|---|---|---|---|
| 1 | NAMEmanual: GRPNAME | A character string of up to eight characters in length that defines the group name for which the network parameters are being defined. The group named FIELD is the top most group and may be used as a GRPNAME. | STRING | None | ||||
| 2 | TERMINAL_manual: PRES | A real value that defines the fixed pressure for this group when the group is a terminating group. If the group is not a terminating group then PRES should be defaulted with 1* or set to a negative number. | DOUBLE | Pressure | psia | barsa | atma | 1* |
| 3 | VFP_manual: VFPTAB | A positive integer greater than or equal to zero that defines the VFPPROD or VFPINJ vertical lift performance table to be used for calculating the pipeline pressures connecting the LOWER and HIGHER groups in the network. Note that: The default value of zero implies that there is no pipeline connecting the LOWER and HIGHER groups. If PRES is set to a real positive number then VFPTAB should be set to zero as this implies that GRPNAME is a terminating group and therefore there is no pipeline connecting GRPNAME to a HIGHER group. If PRES and VFPTAB are defaulted with 1* or zero, then GRPNAME is not part of the network. IF VFPTAB is set equal to 9999 then this implies that there is no pressure change between the LOWER and HIGHER group. If a non-zero value is entered then the vertical lift performance tables must be entered via the VFPPROD or VFPINJ keyword in the SCHEDULE section. | INT | 0 | ||||
| 4 | ALQmanual: ALQ-PIPE | A real positive value that defines the artificial lift quantity to be used in conjunction with the vertical lift performance table (VFPPROD) assigned to the group via VPFTAB variable. The vertical lift performance table and the artificial lift quantity ALQ-WELL are used with the pipeline fluid rates to calculate the pipeline change pressure between the LOWER and HIGHER groups. Note that the units for ALQ-PIPE are dependent on the associated variable on the VFPPROD keyword and may represent a pump or a compressor depending how the VFPPROD table was generated by an external program. | DOUBLE | 0.0 | ||||
| 5 | SUB_manual: OPTION1 | A defined character string that defines if a group’s production target should be achieved by adjusting the tubing pressure of the wells within the group or by the adjusting the well rates by their guide rate. OPTION1 should be set to one of the following character strings: YES: the group production target is achieved by adjusting the tubing pressure of the wells within the group, so that all wells flow at the same tubing head pressure. This is normally used for wells that flow into a common manifold, for example a sub-sea completion manifold. If a group is using this option and has a higher group with production targets or constraints, then this group should have it’s guide rate set via the GCONPROD keyword in the SCHEDULE section, to ensure that the well’s within this group operate at the same tubing head pressure. NO: the group production target is achieved by adjusting the guide rates of the wells within the group. This is the standard method in matching group targets and may result with the wells within the having different tubing head pressures. Only groups containing wells can use OPTION1 equal to YES or NO, a group without wells should set OPTION1 to NO. Numerical convergence controls and iteration limits for wells using OPTION1 set equal to YES are defined via the NETBALAN keyword in the SCHEDULE section. Only the NO option is currently supported by the simulator. | STRING | NO | ||||
| 6 | ADD_manual: OPTION2 | A defined character string that defines if well gas lift gas flows through the group’s pipeline. OPTION2 should be set to one of the following character strings: NO: no well gas lift gas is allowed to flow through the pipeline only produced reservoir gas is allowed to flow through the pipeline. FLO: the well gas lift gas is added to the gas flow along the pipeline. The well gas lift gas is the sum of the calculated ALQ-WELL values for all the subordinate wells multiplied by their efficiency factors. ALQ: the pipeline gas lift gas value (ALQ-PIPE) is the sum of the calculated ALQ-WELL values for all the subordinate wells multiplied by their efficiency factors. This means that the ALQ-PIPE gas lift gas value declared on item (4) is ignored. If either FLO or ALQ have been selected then artificial lift quantity for the pipeline (ALQ-PIPE) and the wells (ALQ-WELL) must be defined as gas lift gas on the VFPPROD tables. A well’s specific gas lift gas quantity is set via the ALQ-WELL variable on the WCONPROD keyword in the SCHEDULE section. Only the NO and FLO options are currently supported by the simulator. | STRING | NO | ||||
| 7 | ALQ_manual: OPTION3 | A defined character string that defines if the ALQ-PIPE variable should be reset to an equivalent surface oil or gas density flowing along the pipeline. OPTION3 should be set to one of the following character strings: DENO: set ALQ-PIPE to the average surface density of the oil flowing along the pipeline. DENG: set ALQ-PIPE to the average surface density of the gas flowing along the pipeline. NONE: no change to ALQ-PIPE. If either DENO or DENG have been selected then artificial lift quantity on the VFPPROD tables must be based on the same density parameter. These options are normally used when a mixture of oil or gas with different surface densities flows into the network. Only the NONE option is currently supported by the simulator. | STRING | NONE |
Example
The following example defines a network based on two groups
--
-- DEFINE GROUP STANDARD NETWORK PARAMETERS
--
-- GRUP CNTL VFP PUMP MANIFOLD INCLUDE ALQ
-- NAME PRES TABLE POWER GROUP LIFT GAS DENS
GRUPNET
PROD-A 1200. 1* /
PROD-B 1* 1 1* 'YES' 1* 1* /
/
The next example is more complex and is taken form the Norne model.
--
-- DEFINE GROUP STANDARD NETWORK PARAMETERS
--
-- GRUP CNTL VFP PUMP MANIFOLD INCLUDE ALQ
-- NAME PRES TABLE POWER GROUP LIFT GAS DENS
GRUPNET
FIELD 20.0 5* /
PROD 20.0 5* /
MANI-B2 1* 8 1* NO 2* /
MANI-B1 1* 8 1* NO 2* /
MANI-K1 1* 9999 4* /
B1-DUMMY 1* 9999 4* /
MANI-D1 1* 8 1* NO 2* /
MANI-D2 1* 8 1* NO 2* /
MANI-K2 1* 9999 4* /
D2-DUMMY 1* 9999 4* /
MANI-E1 1* 9 1* NO 2* /
MANI-E2 1* 9 4* /
/
Here the FIELD group controlling pressure is set at 20 barsa and the same limit is used for group PROD which sits directly under the FIELD group (see Figure 12.4).Related keywords
- Cannot be combined with
NETWORK,BRANPROP,NODEPROP
Manual source: parts/chapters/subsections/12.3/GRUPNET.fodt