Parent Command
>> FLOW

Subcommand
all fourth-level commands in block > OBSERVATION

Description
This command reads pairs of element names defining a connection. Element names are designated by a three-character/two-integer (FORTRAN format: AAAII) code name. Blanks in the element names as printed in the TOUGH2 output file must be replaced by underscores (e.g., an element name specified in the TOUGH2 input file as 'B 007' is printed as 'B 0 7' to the TOUGH2 output file. Therefore, it must be addressed in the iTOUGH2 input file as 'B_0_7'). Multiple connections can be specified, and iTOUGH2 calculates the sum or mean of all flow rates (see subcommands >>>> SUM and >>>> AVERAGE, respectively). A sequence of iplus connections can be generated where the number found in the substring [islotb-islote] (default: [4-last]) of the first and/or the second element is increased by 1. If only the first (second) element in a sequence of connections should be increased, use +- (-+). If both elements are to be increased, use + (or ++). The following two command lines are thus identical:

>>> CONNECTION: AA__1 BB_15 -+ 2 [4-5]
>>> CONNECTION: AA__1 BB_15 AA__1 BB_16 AA__1 BB_17

If keyword COORDINATES is present, coordinates can be specified, and the connection closest to these coordinates will be identified. If keywords COORDINATE BOX or COORDINATE RANGE are present, all connections within the specified box will be included in the connection list. Element coordinates must be present in columns 51–80 of the TOUGH2 ELEME block. If keyword PROFILE, CROSS-SECTION, or MAP is present, the data (which must be provided in an external file, see command >>>> DATA FILE: filename) are organized spatially by lists of coordinates followed by columns of measured values for each survey time. The data will be assigned to the nearest connection (element coordinates must be present in columns 51–80 of the TOUGH2 ELEME block.). Keyword PROFILE supports one-dimensionl, vertical data profiles (i.e., Z-coordinates), whereas CROSS-SECTION and MAP both require X-, Y-, and Z-coordinates. Profile data are given as follows:

NZ NT
XCoord YCoord
Time(1) Time(2) ... Time(NT)
Z(1) Data(1,1) Data(1,2) ... Data(1,NT)
Z(2) Data(2,1) Data(2,2) ... Data(2,NT)
... ... ... ... ...
Z(NZ) Data(NZ,1) Data(NZ,2) ... Data(NZ,NT)

Two- or three-dimensional data are given as follows:

NP NT
Time(1) Time(2) ... Time(NT)
X(1) Y(1) Z(1) Data(1,1) Data(1,2) ... Data(1,NT)
X(2) Y(2) Z(2) Data(2,1) Data(2,2) ... Data(2,NT)
... ... ... ... ... ... ...
X(NP) Y(NP) Z(NP) Data(NP,1) Data(NP,2) ... Data(NP,NT)

Example
> OBSERVATION
>> LIQUID FLOW RATE
>>> list of CONNECTIONS: ELM_1 ELM_2 + 48
>>>> ANNOTATION : Boundary flux
>>>> take the SUM of the flow rates across 49 connections
>>>> DATA on FILE : flow.dat
>>>> RELATIVE error: 10 %
<<<<
>> GAS FLOW RATE
>>> all CONNECTIONS in COORDINATE BOX: -1000 -1000 -1 1000 1000 1
>>>> ANNOTATION : Surface gas release
>>>> take SUM of flow rates across surface
>>>> HEADER : 2
>>>> COLUMNS : 1 3
>>>> DATA on FILE : flow.dat
>>>> RELATIVE error: 10 %
<<<<
<<<
<<

See Also
>>>> AVERAGE | >>>> SUM