WELTRAJ

Recognised by the OPM Flow parserSCHEDULE

The WELTRAJ keyword defines a grid-independent well together with the well trajectory data (simplified directional survey data), and is used in conjunction with the COMPTRAJ keyword in the SCHEDULE section to define the well connections to the simulation grid blocks. The keyword can only be used for grid-independent wells that employ the COMPTRAJ keyword to define the connections to the grid, that is, one cannot use COMPDAT keyword in the SCHEDULE section for declaring the connections to the grid for these type of wells.

Although WELTRAJ and COMPTRAJ keywords are sufficient to define the wellbore path and connections to the grid, it is still necessary to defined the general well specification parameters using the WELSPECS keyword in the SCHEDULE section. In this case, the wellhead location parameters, WELSPECS(I, J), should be defaulted with 1*.

Note

This is an OPM Flow specific keyword and will therefore cause an error in the commercial simulator.

Notes:

For this keyword the Laboratory set of units are not supported.

The keyword is followed by any number records with each record terminated by a “/” and the keyword should be terminated by a “/”.

Note that the total number of individual wells declared by the WELSPECS cannot exceed the valued entered via the MXWELS variable on the WELLDIMS keyword in the RUNSPEC section.

OPM Flow currently provides partial support for grid-independent multi-segment wells. If a grid-independent well is defined as a multi-segment well using the WELSEGS keyword without defining the segment structure (i.e. only the first record is defined and the keyword is terminated by a slash), information provided by the WELTRAJ and COMPTRAJ keywords is used to generate the well segments (i.e. the missing WELSEGS records, and the COMPSEGS information). However, if the WELSEGS keyword defines the segment structure for a grid-independent well (i.e two or more records are defined) then an error will be reported.

The internally generated multi-segment well's segment structure currently consists of one segment for each cell along the well trajectory as defined by the WELTRAJ keyword. The tubing internal diameter is currently set equal to the wellbore diameter specified on the COMPDAT keyword and the tubing roughness is set to zero. Future developments are expected to support reading additional WELSEGS records to give more control over the segment structure and tubing properties. The well connections defined by the COMPTRAJ keyword are currently allocated to the nearest well segment.

Using the WELTRAJ and COMPTRAJ keywords to define wells and how they are connected to grid, offers several advantages compared to the conventional approach based on the (I, J, K) co-ordinates of the grid. The approach allows for the wells to be independent of the grid, which is particularly useful when running ensemble cases, as the well connections are no longer required to be re-calculated for each ensemble case. In addition, quality control of the model is improved by using consistent perforation data in both the static and dynamic models.

See the example on the following page.

Records

One or more records, each terminated by /

Items per record

6

Parameters

Example

The following example defines two grid-independent standard oil wells, OP01 and OP02, using the WELSPECS and WELTRAJ keywords, together with their perforations using the COMPTRAJ keyword.
--
-- WELL SPECIFICATION DATA
--
-- WELL GROUP LOCATION BHP PHASE DRAIN INFLOW OPEN CROSS PVT
-- NAME NAME I J DEPTH FLUID AREA EQUANS SHUT FLOW TABLE
WELSPECS
OP01 PLATFORM 1* 1* 1* OIL 1* STD SHUT NO 1* /
OP02 PLATFORM 1* 1* 1* OIL 1* STD SHUT NO 1* /
/
--
-- WELL TRAJECTORY DATA
--
-- WELL BRAN XCORD YCORD TVDSS MD
-- NAME NO DEPTH DEPTH
-- ----- ---- ------------ ------------ ------------ ------------
WELTRAJ
OP01 1* 2.805445e+06 3.602948e+06 -100.000000 0.0 /
OP01 1* 2.805445e+06 3.602948e+06 877.0000000 977.0 /
OP01 1* 2.805445e+06 3.602948e+06 957.9950240 1058.0 /
OP01 1* 2.805444e+06 3.602946e+06 1051.976081 1152.0 /
…………………... /
OP02 1* 2.810828e+06 3.604507e+06 9371.792711 11418.0 /
OP02 1* 2.810885e+06 3.604525e+06 9443.657000 11511.0 /
OP02 1* 2.810952e+06 3.604546e+06 9531.966162 11624.0 /
OP02 1* 2.810973e+06 3.604553e+06 9560.411742 11660.0 /
/
--
--
-- WELL TRAJECTORY CONNECTION DATA
--
-- WELL BRAN -- PERFORATION -- COMPL OPEN SAT CONN WELL KH SKIN D
-- NAME NO. TOP BOT REF NO. SHUT TAB FACT DIA FACT FACT FACT
COMPTRAJ
OP01 1* 8230 8244 MD 1 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 8352 8380 MD 1 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 9070 9100 MD 1 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 9220 9250 MD 2 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 9266 9280 MD 2 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 9693 9703 MD 3 SHUT 1* 1* 0.708 1* 0.0 1* /
OP01 1* 9940 9974 MD 3 SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 9979 9985 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 10173 10183 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 10190 10204 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 10327 10333 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 10339 10345 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
OP02 1* 11528 11538 TVD 1* SHUT 1* 1* 0.708 1* 0.0 1* /
Here, well OP01 has eight perforation intervals, with the intervals one to three grouped into one completion, perforation intervals four to five grouped into completion number two, and finally the bottom three perforations are grouped into completion number three. In contrast, OP02 has six perforated intervals with their completion interval defaulted to one.
| Note This is an OPM Flow specific keyword and will therefore cause an error in the commercial simulator. |
|----------------------------------------------------------------------------------------------------------|

Manual source: parts/chapters/subsections/12.3/WELTRAJ.fodt