WSEGVALV

Recognised by the OPM Flow parserSCHEDULE

The WSEGVALV keyword defines a multi-segment well segment to be a sub-critical valve Inflow Control Device (“ICD”) as part of a completion for a multi-segment well. Note that the well must have been previously defined by the WELSPECS and WELSEGS keywords in the SCHEDULE section and that the data for the keyword should be repeated for each multi-segment completion that contains a sub-critical valve ICD.

An ICD is a well completion component usually installed along the producing section of a well to minimize the unwanted water and gas breakthrough in an oil well, or early water production in a gas well, due to an uneven flow profile over the completed interval. Permeability variations over the producing interval cause the high permeability zones to produce higher quantities of fluids than the lower permeability zones and this uneven producing fluid profile may result in bypassed hydrocarbons. Secondly, for horizontal wells, the pressure loss from the “toe” to the “heel” of the well again results in an uneven fluid profile over the producing interval. In order to rectify this ICDs can be installed so that the well fluids have to flow through an ICD before entering the tubing; thus, creating an additional “designed” pressure loss.

A sub-critical valve ICD is a type of frictional ICD that adds an additional pressure loss by directing the fluid through a constriction before entering the tubing. The pressure drop is a function of the fluid density, the volumetric flow rate, and the diameter of the constriction. By placing various ICD’s over the production interval one can design a completion that results in a more uniform producing fluid profile throughout the length of the producing interval.

Notes:

User Defined Quantities ("UDQ") can be used as User Defined Arguments ("UDA") for various group, well, and connection keywords in the SCHEDULE section. User Defined Arguments are activated using the UDADIMS keyword in the RUNSPEC section, and defined by the UDQ keyword in the SCHEDULE section.

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

The total number of wells should be defined via the WELLDIMS keyword and the number of multi-segment wells should be declared on the WSEGDIMS keyword, both keywords are in the RUNSPEC section. In addition, the WELSPECS keyword should be used to define wells, the COMPDAT keyword to define the well completions for both ordinary wells and multi-segment wells, and the COMPSEGS keyword to define a multi-segment segment completions.Finally, the WSEGVALV keyword can then be use to define ICD connections for the well. All the aforementioned keywords are described in the SCHEDULE section.

OPM flow calculates the pressure drop across the ICD using a homogeneous sub-critical flow through a constriction model. The model consists of two variables, the pressure drop due to the constriction,[%delta P sub restriction], and the pressure drop due to friction,, and the pressure drop due to friction,[%delta P sub friction], as shown in equation , as shown in equation (12.42).

[%delta P ~=~ %delta P sub restriction ``+``%delta P sub friction newline newline where newline %delta P sub restriction ``=``C sub 1 {%rho {%upsilon sup 2} sub r} over { 2{C sub v} }sup 2 newline newline %delta P sub friction ``=`` 2C sub 2 f L over D %upsilon sup 2 sub p]

(12.42)

Where:

C1 and C2=Unit conversion constants as listed in Table 12.122.

Cv= Vendor supplied dimensionless flow coefficient for the valve.

D=Diameter of the pipe.

f=Fanning friction factor.

L=Segment pipe length.

ρ=Fluid mixture density.

υr=The flow velocity of the mixture through the constriction.

υp=The flow velocity of the mixture through the segment pipe.

Conversion Factor Constants and Variable Units

In addition as both υr and υp are dependent on their respective cross-section areas then the volumetric flow (q) through the device requires that:

[q ``=``%upsilon sub r A sub r ``=``%upsilon sub p A sub p]

(12.43)

Substituting equation (12.43)for[%delta P sub restriction]in equation in equation (12.42)one obtains:

[%delta P sub restriction ``=``C sub 2 {%rho {q} sup 2} over {{ 2{C sub v} }sup 2 A sup 2 sub r}]

(12.44)

Where:

Ar=Cross-sectional area of the constriction.

C2=Unit conversion constants as listed in Table 12.122.

Cv= Vendor supplied dimensionless flow coefficient for the valve.

ρ=Fluid mixture density.

q= Volumetric flow rate.

The base strength of the device, K is defined using equation (12.44)as follows:

[K ``=` {`C sub 2} over {{ 2{C sub v} }sup 2 A sup 2 sub r}]

(12.45)

Note if K is greater than 0.1 then the device will be shut.

The setting of the device, that is how open the device is, is related to the restricted area and the maximum restricted area of the device as follows:

[Seting of Device ``=`` { A sub r } over { A sub max }]

(12.46)

Where:

Ar=Cross-sectional area of the constriction.

Amax=Maximum cross-sectional area of the constriction.

Records

One or more records, each terminated by /

Items per record

10

Parameters

Example

The following example is based on one producing well segment oil well (OP01) using the WELSPECS, WELSEGS COMPDAT and COMPSEGS keywords, as per the WSEGSICD keyword example (Example), and is therefore not repeated here.
--
-- MULTI-SEGMENT WELL ICD SEGMENT SPECIFICATION DATA
--
-- WELL SEG DEVICE AREA PIPE PIPE PIPE PIPE OPEN MAX
-- NAME NO CV REST LENG ID EPSI AREA SHUT AREA
WSEGVALV OP01 7 0.960 0.012 1* 1* 1* 1* OPEN 1* / DEFAULT VALUES
OP01 12 0.960 0.012 1* 1* 1* 1* OPEN 1* / TAKEN FROM
OP01 17 0.960 0.012 1* 1* 1* 1* OPEN 1* / WELSEGS KEYWORD
OP01 22 0.850 0.100 1* 1* 1* 1* OPEN 1* /
OP01 23 0.850 0.100 1* 1* 1* 1* OPEN 1* /
OP01 24 0.850 0.100 1* 1* 1* 1* OPEN 1* /
OP01 25 0.850 0.100 1* 1* 1* 1* OPEN 1* /
/
Here segments 7, 12 and 17 have the same type of sub-critical valves with their pipe properties taken from the WELSEGS keyword used to define well OP01 as a multi-segment well. Similarly, segments 22 to 25 have the same ICD properties, and again the pipe properties are taken from the WELSEGS keyword.
| [%delta P ~=~ %delta P sub restriction ``+``%delta P sub friction newline
newline
where  newline
%delta P sub restriction ``=``C sub 1 {%rho {%upsilon sup 2} sub r} over { 2{C sub v} }sup 2 newline
newline
%delta P sub friction ``=`` 2C sub 2 f L over D %upsilon sup 2 sub p] | (12.42) |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------|
| Conversion Factor Constants and Variable Units |                 |               |               |               |          |
|------------------------------------------------|-----------------|---------------|---------------|---------------|----------|
| No.                                            | Name            | Field         | Metric        | Laboratory    | Property |
| 1                                              | C1              | 2.159 x 10-4  | 1.0 x 10-5    | 9.869 x 10-7  | Constant |
| 2                                              | C2              | 2.892 x 10-14 | 1.340 x 10-15 | 7.615 x 10-14 |          |
| 3                                              | Density         | lb/ft3        | kg/m3         | gm/cc         | Units    |
| 4                                              | Pressure        | psia          | bars          | atm           |          |
| 5                                              | Velocity        | ft/s          | m/s           | cm/s          |          |
| 6                                              | Volumetric Flow | ft3/day       | m3/day        | cc/hour       |          |
| [q ``=``%upsilon sub r A sub r ``=``%upsilon sub p A sub p] | (12.43) |
|-------------------------------------------------------------|---------|
| [%delta P sub restriction ``=``C sub 2 {%rho {q} sup 2} over {{ 2{C sub v} }sup 2 A sup 2 sub r}] | (12.44) |
|---------------------------------------------------------------------------------------------------|---------|
| [K ``=` {`C sub 2} over {{ 2{C sub v} }sup 2 A sup 2 sub r}] | (12.45) |
|--------------------------------------------------------------|---------|
| [Seting of Device ``=`` { A sub r } over { A sub max }] | (12.46) |
|---------------------------------------------------------|---------|

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