UTL-TVK

Structure of Blocks

FOR EACH SIMULATION

    BEGIN OPTIONS
      [PRINT_INPUT]
      [TS6 FILEIN <ts6_filename>]
    END OPTIONS

FOR ANY STRESS PERIOD

    BEGIN PERIOD <iper>
      <cellid(ncelldim)> <tvksetting>
      <cellid(ncelldim)> <tvksetting>
      ...
    END PERIOD

Explanation of Variables

Block: OPTIONS

PRINT_INPUT keyword to indicate that information for each change to the hydraulic conductivity in a cell will be written to the model listing file.
TS6 keyword to specify that record corresponds to a time-series file.
FILEIN keyword to specify that an input filename is expected next.
ts6_filename defines a time-series file defining time series that can be used to assign time-varying values. See the “Time-Variable Input” section for instructions on using the time-series capability.

Block: PERIOD

iper integer value specifying the starting stress period number for which the data specified in the PERIOD block apply. IPER must be less than or equal to NPER in the TDIS Package and greater than zero. The IPER value assigned to a stress period block must be greater than the IPER value assigned for the previous PERIOD block. The information specified in the PERIOD block will continue to apply for all subsequent stress periods, unless the program encounters another PERIOD block.
cellid is the cell identifier, and depends on the type of grid that is used for the simulation. For a structured grid that uses the DIS input file, CELLID is the layer, row, and column. For a grid that uses the DISV input file, CELLID is the layer and CELL2D number. If the model uses the unstructured discretization (DISU) input file, CELLID is the node number for the cell.
tvksetting line of information that is parsed into a property name keyword and values. Property name keywords that can be used to start the TVKSETTING string include: K, K22, and K33.
```
  K <k>
  K22 <k22>
  K33 <k33>
```
k is the new value to be assigned as the cell’s hydraulic conductivity from the start of the specified stress period, as per K in the NPF package. If the OPTIONS block includes a TS6 entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.
k22 is the new value to be assigned as the cell’s hydraulic conductivity of the second ellipsoid axis (or the ratio of K22/K if the K22OVERK NPF package option is specified) from the start of the specified stress period, as per K22 in the NPF package. For an unrotated case this is the hydraulic conductivity in the y direction. If the OPTIONS block includes a TS6 entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.
k33 is the new value to be assigned as the cell’s hydraulic conductivity of the third ellipsoid axis (or the ratio of K33/K if the K33OVERK NPF package option is specified) from the start of the specified stress period, as per K33 in the NPF package. For an unrotated case, this is the vertical hydraulic conductivity. If the OPTIONS block includes a TS6 entry (see the “Time-Variable Input” section), values can be obtained from a time series by entering the time-series name in place of a numeric value.

Example Input File

    BEGIN OPTIONS
      TS6 FILEIN tvk_cells.ts
      # Note: Time-series file tvk_cells.ts defines time series cells_kz
    END OPTIONS
    
    # Cell 5 will have its K value changed to 1e-3 in the first time step of
    # stress period 2, and changed once more to 1e-4 in the first time step of
    # stress period 4.
    #
    # Cells 101 and 108 will have their respective K33 values changed according
    # to the time series cells_kz specified in the file tvk_cells.ts. Note that
    # these values may continue to change beyond stress period 2, depending on
    # the duration of the time series cells_sy.
    #
    # No changes are made in stress period 1 due to an absence of a block
    # for that period; cells maintain the initial property values specified in
    # the NPF package for the entirety of that period.
    
    BEGIN PERIOD 2
      5   K   1e-3
      101 K33 cells_kz
      108 K33 cells_kz
    END PERIOD
    
    BEGIN PERIOD 4
      5   K   1e-4
    END PERIOD
    
    # After the last specified change (or after the last specified time record,
    # when a time series is used), each affected cell will retain its latest
    # changed value for the remainder of the simulation.