`PVTWSALT`

Recognised by the OPM Flow parserPROPS

PVTWSALT defines the brine water properties for various regions in the model, for when the brine phase has been activated by the BRINE keyword in the RUNSPEC section. In this case PVTWSALT is used instead of PVTW in the input file. However, if the ECLMC keyword has been entered in the RUNSPEC section to invoke the Multi-Component Brine model, the PVTW keyword should be used instead of PVTWSALT, as with this combination the salinity effect on the density is ignored.

The number of PVTWSALT table data sets is defined by the NTPVT parameter on the TABDIMS keyword in the RUNSPEC section and the allocation of the PVTWSALT tables to different grid blocks in the model is done via the PVTNUM keyword in the REGIONS section.

Notes:

The keyword is followed by NTPVT data sets as declared on the TABDIMS keyword in the RUNSPEC section and each data set consists of two records, with items 1-1 to 1-3 representing record one items and 2-1 to 2-6 representing record number two items, etc., in the “No.” column in this table.

Each table must contain a minimum of two rows and a maximum of NPPVT rows as declared on the TABDIMS keyword in the RUNSPEC section.

Each table is terminated by a “/” and there is no “/” terminator for the keyword.

As mentioned above, the simulator first calculates the water properties as functions of the salt concentration at the previous time step by linear interpolation in salt concentration for water compressibility (Cw), water viscosibility (μwc), [1 over B sub{ w}]andand[1 over { B sub{w}`` %mu sub{w} }]. . It then calculates the values of[B sub{ w}]andand[B sub{w}`` %mu sub{w}]at the current time step using the current pressure P, using the following equations:at the current time step using the current pressure P, using the following equations:

[{ B _ w ( { P , C _ s } ) `` = `` { { B _ w ( { P _ ref , C _ {s, ref} } ) } over { 1 ` + ` C _ w ( P - P _ ref ) ` + ` { left ( { C _ w ( P - P _ ref ) } right ) ^ 2 over 2 } } } }]

(8.82)

and

[{ B _ w ( { P , C _ s } ) `` %mu _ w ( { P , C _ s } ) `` = `` { { B _ w ( { P _ ref , C _ {s, ref} } ) `` %mu _ w ( { P_ref , C _ {s, ref} } ) } over { 1 ` + ` ( { C _w - `` %mu _ wc } ) ( P - P _ ref ) ` + ` { left ( { ( C _ w - ``%mu _ wc ) ( P - P _ ref ) } right ) ^ 2 over 2 } } } }]

(8.83)

See also the BDENSITY keyword in the PROPS section that defines the brine surface densities for the salt concentrations declared on the PVTWSALT keyword. Note that if the BDENSITY keyword is absent from the input file then the brine surface densities will be set to the water density values declared via the DENSITY keyword in the PROPS section. In this case there is no variation in brine surface density with respect to salt concentration.

Records: Fixed number of records

Parameters

No.	Name	Description	Field	Metric	Lab	Default
1	`PRESS`	Single real positive value that defines the reference pressure for the data in the following records (Pref). PRESS should be approximately equal to the average reservoir pressures in the model. The simulator uses the previous time step values to forecast the current time step water properties by linear interpolation. If PRESS is not representative of the average reservoir pressures in the model then the linear interpolation might result in nonphysical values of the water saturation and water viscosity.	psia	barsa	atma	None
1			lb/stb	kg/sm3	gm/scc
1	`SALTCON`	A columnar vector of real monotonically increasing values that defines the salt concentration in the solution (Cs).	lb/stb	kg/sm3	gm/scc	None
1			rb/stb	rm3/sm3	rcc/scc
3	`WCOMP`	WCOMP is a real columnar vector defining the water compressibility (Cw) at the water reference pressure PRESS, for the corresponding salt concentration SALTCON. The water compressibility is defined as: [C sub{w}~=~ - 1 over {B sub{w}}left({dB sub{w}} over{dP} right)]	1/psia	1/bars	1/atma	None

Example

The following shows the PVTWSALT keyword for when NTPVT on the TABDIMS keyword in the RUNSPEC section is set equal to two and NPPVT is set to greater than four on the TABDIMS keyword.
--
-- WATER SALT PVT TABLE
--
PVTWSALT
-- REF PRES REF SALT
-- PSIA LB/STB
-- -------- --------
4500.0 0.000 / TABLE NO. REF. DATA
--
-- SALTCONBW CW VISC VISC
-- LB/STB RB/STB 1/PSIA CPOISE GRAD
-- -------- -------- ------- ------ ------
0.0 1.020 2.7E-6 0.370 0.0
2.0 1.010 2.7E-6 0.370 0.0
4.0 1.000 2.7E-6 0.370 0.0
10.0 0.950 2.7E-6 0.370 0.0 / TABLE NO. 01 SALT DATA
--
-- REF PRES REF SALT
-- PSIA LB/STB
-- -------- --------
4000.0 0.000 / TABLE NO. 02 REF. DATA
--
-- SALTCON BW CW VISC VISC
-- LB/STB RB/STB 1/PSIA CPOISE GRAD
-- -------- -------- ------- ------ ------
0.0 1.005 2.5E-6 0.320 0.0
3.0 1.000 2.5E-6 0.320 0.0
6.0 0.985 2.5E-6 0.320 0.0
12.0 0.930 2.5E-6 0.320 0.0 / TABLE NO. 02 SALT DATA
Note that each table is terminated by a “/” and there is no “/” terminator for the keyword.
| 1-1 |
|-----|
| 2-1 |
|-----|
| [{ B _ w ( { P , C _ s } ) `` = `` { { B _ w ( { P _ ref , C _ {s, ref} } ) } over { 1 ` + ` C _ w ( P - P _ ref ) ` + ` { left ( { C _ w ( P - P _ ref ) } right ) ^ 2 over 2 } } } }] | (8.82) |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|
| [{ B _ w ( { P , C _ s } ) `` %mu _ w ( { P , C _ s } ) `` = `` { { B _ w ( { P _ ref , C _ {s, ref} } ) `` %mu _ w ( { P_ref , C _ {s, ref} } ) } over { 1 ` + ` ( { C _w - `` %mu _ wc } ) ( P - P _ ref ) ` + ` { left ( { ( C _ w - ``%mu _ wc ) ( P - P _ ref ) } right ) ^ 2 over 2 } } } }] | (8.83) |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------|

Manual source: parts/chapters/subsections/8.3/PVTWSALT.fodt