TUNINGS

Recognised by the OPM Flow parserSCHEDULE

TUNINGS defines the parameters used for controlling the commercial simulator’s numerical convergence parameters for individual Local Grid Refinements ("LGR"). The keyword is similar to the TUNINGL keyword in the SCHEDULE section that applies the tuning parameters to the all LGRs, except for an additional first record that includes the LGR name.

This keyword is not supported by OPM Flow but has no effect on the results so it will be ignored.

See section 2.2Running OPM Flow 2023-04 From The Command Lineon how to invoke various numerical schemes via the OPM Flow command line interface.

Notes:

The keyword consists of three records, with items 1-1 to 1-11 representing record one items, 2-1 to 2-14 record two and 3-1 to 3-12 representing record number three. Each of the records are terminated by a “/” and is explicitly shown in the above rows.

There is no keyword terminating “/”.

Note that for record number two (items 2-1 to 2-13) the maximum values should always be greater than the associated target value; for example, XXXCNV should be greater than TRGCNV. Also note that the TUNING keyword is stored on the restart files (see RPTRST – Define Data to be Written to the RESTART File) enabling the parameters to be utilized in a restart run without re-specifying the keyword.

See also the TUNINGL keyword in the SCHEDULE section that sets the tuning parameters for all LGRs.

Records
Fixed number of records
Record count
4
Items per record
record 1: 1, record 2: 10, record 3: 13, record 4: 11

Parameters

Record 1

No.NameDescriptionTypeDimensionFieldMetricLabDefault
1LGR
manual: LGRNAME
A character string of up to eight characters in length that defines the LGR name for which the tuning data is being being defined.STRINGNone

Record 2

No.NameDescriptionTypeDimensionFieldMetricLabDefault
1TSINITTSINT is a real positive value that defines the maximum length of the next time step. Note that whenever the keyword is used TSINIT is always set back to the default value of one, unless explicitly over written.DOUBLETimedaysdayshours1.0
2TSMAXZTSMAXZ is a real positive value that defines the maximum length of the next time step following TSINIT.DOUBLETimedaysdayshours365.0
3TSMINZTSMINZ is a real positive value that defines the minimum length of all time steps.DOUBLETimedaysdayshours0.1
4TSMCHPTSMCHP is a real positive value that sets the minimum length of all chopped time steps.DOUBLETimedaysdayshours0.15
5TSFMAXTSFMAX is a real positive value that specifies the maximum growth rate a time step can be increased by, subject to the maximum allowable time step size set by TSMAXZ. For example, if the current time step has converged at 10 days and TSFMAX is set to the default value, then the next time step will be 3.0 x 10 days, that is 30 days provided it is less than TSMAXZ.DOUBLEdimensionlessdimensionlessdimensionless3.0
6TSFMINTSFMIN is a real positive value that specifies the minimum decay rate a time step can be decreased by, subject to the minimum allowable time step size set by TSMINZ. For example, if the current time step has not converged at 10 days and TSFMAX is set to the default value, then the next time step will be 0.3 x 10 days, that is the maximum of 0.3 days and TSMINZ.DOUBLEdimensionlessdimensionlessdimensionless0.3
7TSFCNVTSFCNV real positive value that specifies the decay rate a time step can be decreased by after the number of target iterations has been exceeded.DOUBLEdimensionlessdimensionlessdimensionless0.1
8TFDIFFTFDIFFA is a real positive value that sets the time step growth factor of the time step after a convergence failure. For example, if the chopped current convergent time step is 10 days and TFDIFF is set to the default value, then the time step will be increased to 1.25 x 10 days, that is the minimum of 11.25 days and TSMAXZ.DOUBLEdimensionlessdimensionlessdimensionless1.25
9THRUPT
manual: THRURPT
THRURPT is a real positive value that specifies the maximum throughput ratio over a time step.DOUBLEdimensionlessdimensionlessdimensionless1.0 x 1020
10TMAXWCTMAXWC is a real double precision value that defines maximum allowed time step after a well event; for example, when a well is opened or closed, etc.DOUBLETimedaysdayshoursNone

Record 3

No.NameDescriptionTypeDimensionFieldMetricLabDefault
1TRGTTETRGTTE is a real positive value that sets the time truncation error target.DOUBLEdimensionlessdimensionlessdimensionless0.1
2TRGCNVTRGCNV a real positive value that defines the non-linear convergence error.DOUBLEdimensionlessdimensionlessdimensionless0.001
3TRGMBETRGMBE is a real positive value that specifies then target material balance error.DOUBLEdimensionlessdimensionlessdimensionless1.0 x 10-7
4TRGLCVTRGLCV is a real positive value that specifies the linear convergence error target.DOUBLEdimensionlessdimensionlessdimensionless0.00001
5XXXTTEXXXTTE is a real positive value that sets the maximum time truncation error.DOUBLEdimensionlessdimensionlessdimensionless10.0
6XXXCNVXXXCNV is a real positive value that defines the maximum non-linear convergence error.DOUBLEdimensionlessdimensionlessdimensionless0.01
7XXXMBEXXXMBE is a real positive value that specifies the maximum mass balance error, that is the tolerated mass balance error relative to total mass present.DOUBLEdimensionlessdimensionlessdimensionless1.0 x 10-6
8XXXLCVXXXLCV is a real positive value that sets the maximum linear convergence error.DOUBLEdimensionlessdimensionlessdimensionless0.0001
9XXXWFLXXXWFL is a real positive value that fixes the maximum well flow convergence error.DOUBLEdimensionlessdimensionlessdimensionless0.001
10TRGFIPTRGFIP is a real positive value that stipulates the target fluid in-place error in Local Grid Refinements.DOUBLEdimensionlessdimensionlessdimensionless0.025
11TRGSFTTRGSFT is a real positive value that defines the target surfactant change when the Surfactant Model is active in the run.DOUBLEdimensionlessdimensionlessdimensionlessNone
12THIONXTHIONX is a positive real value used to set the threshold for damping in the ion echange calculation for when the Brine Model is active in the run.DOUBLEdimensionlessdimensionlessdimensionless0.01
13TRWGHTTRWGHT is a positive integer that stipulates the implicitness for active tracer updates within the Newton iterations, and should be set to: The calculation is explicit, that is fully decoupled. The calculation is implicit, that is fully coupled.INTdimensionlessdimensionlessdimensionless1

Record 4

No.NameDescriptionTypeDimensionFieldMetricLabDefault
1NEWTMXNEWTMX is a positive integer greater or equal to NEWTMN that stipulates the maximum number of Newton iterations for a time step.INTdimensionlessdimensionlessdimensionless12
2NEWTMNNEWTMN is a positive integer that is less or equal to NEWTMX that defines the minimum number of Newton iterations for a time step.INTdimensionlessdimensionlessdimensionless1
3LITMAXLITMAX is a positive integer greater or equal to LITMIN that sets the maximum number of linear iterations within a Newton iteration.INTdimensionlessdimensionlessdimensionless25
4LITMINLITMIN is a positive integer less or equal to LITMAX that sets the minimum number of linear iterations within a Newton iteration.INTdimensionlessdimensionlessdimensionless1
5MXWSITMXWSIT is a positive integer that defines the maximum number of iterations within a well flow calculation.INTdimensionlessdimensionlessdimensionless8
6MXWPITMXWPIT is a positive integer that stipulates the maximum number of iterations for solving the bottom-hole pressure for wells under tubing head pressure control within a well flow calculation.INTdimensionlessdimensionlessdimensionless8
7DDPLIMDDPLIM a real positive value that stipulates the maximum pressure change at the last Newton iteration.DOUBLEPressurepsiabarsaatma1.0 x 10-6
8DDSLIMDDSLIM a real positive value that sets the maximum saturation change at the last Newton iteration.DOUBLEdimensionlessdimensionlessdimensionless1.0 x 10-6
9TRGDPRTRGDP is a real positive value that defines the target pressure change within a time step.DOUBLEPressurepsiabarsaatma1.0 x 10-6
10XXXDPRXXXDPR is a real positive value that stipulates the maximum tolerable pressure change within a time step.DOUBLEPressurepsiabarsaatma1.0 x 10-6
11MNWRFPMNWRFP is a positive integer greater than one and less than NEWTMX that defines the minimum number of Newton iterations before invoking the bisection algorithm for when the polymer phase is active in the model via the POLYMER keyword in the RUNSPEC section.INTdimensionlessdimensionlessdimensionless4

Example

--
-- DEFAULT TUNINGS PARAMETERS
--
TUNINGS
OP01-LGR
/
/
/
The above example explicitly sets the default parameters for the LGR named OP01-LGR

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