K MODEL.DAT

Basic Information

File-Type

k_model.dat

File-Form

FORMATTED

Version

January 2020

Description-Date

January 2020

Significance of the File

contains specific input data related to the software package (k-model).

File-Contents (in Catchwords)

1. block Test_Output to specify the level of datail for test output:
   1. key "Level" to steer the level of detail for test output with allowed values None, Low, Moderate, Medium, High and Extreme.
2. block Start_Restart_Specifications different informations related to initial state:
   1. key "Cold_Start" with possible values Yes or No  :

      if Yes, initial state will be constructed from data given in block Initial_Spectra; ;

      if No, initial data will be read from previously generated files

      • BLFYYYYMMDDhhmmss and
      • LAFYYYYMMDDhhmmss.

      These files must be available at start time YYYYMMDDhhmmss in the local working directory.

   2. key "Restart_Output_Timestep" with time step for output of restart files

      • BLFYYYYMMDDhhmmss und
      • LAFYYYYMMDDhhmmss.

      Restart files can be used in a later run to read the initial state from file.

3. block Initial_Spectra for a more detailed description of the initial state if Cold_Start=Yes was chosen:
   1. key "Type_Of_Spectra" describes the type of initial spectrum used; the following options exist:
      1. "Energy_Equal_Zero": no waves present;
      2. "Wind_Independent": wind-independent spectrum, which will be computed from subsequent spectra parameters;
      3. "Wind_Dependent": wind-dependent spectrum, which is computed from the subsequently given fetch length as well as the local wind speed valid at start time.
   2. key "Phillips_Parameter", to be computed using program WESPE;
   3. key "Peak_Frequency", to be computed using program WESPE;
   4. key "Overshoot_Factor", to be computed using program WESPE;
   5. key "Left_Peak_Width", to be computed using program WESPE;
   6. key "Right_Peak_Width", to be computed using program WESPE;
   7. key "Wave_Direction", direction, towards which the waves are travelling, e.g. North (0.0 deg) or East (90.0 deg);
   8. key "Fetch", fetch length in (m).
4. block Timestep_For_Integration contains different time step data:
   1. key "Propagation_Timestep", time step for propagation of waves, as well as depth- and current refraction; if the user-prescribed time

      step violates the CFL-condition, the time step will be halved as often as necessary to fulfill the CFL-condition and therefore an emergency

      stop of the running program will no longer occur; the time step used internally will never be larger than the one prescribed by the user;

   2. key "Source_Timestep", time step for sources and sinks (wind, nonlinear dissipation, dissipation due to bottom interaction);
   3. key "Ratio_Propagation_Refraction", integer number to describe the ratio between sub steps for propagation and refraction.
5. block Options with steering data for consideration of time- and space-varying water depth as well as current velocity and computation of radiation

   stress as well as various steering parameters for interpolation of boundary values as well as computational results between different grids:

   1. key "Depth_Option" to describe the influence of water depth:
      1. Deep_Water: deep water approximation;
      2. Time_Variable_Depth: transient water depth
   2. key "Current_Option" to describe the influence of current velocity:
      1. No_Current: no influence due to currents;;
      2. Time_Variable_Current: transient cuurrent velocity
   3. key "Radiation_Option" to trigger computation of radiation stress terms:
      1. No_Radiation_Stress: radiation stress terms will not be computed;
      2. With_Radiation_Stress: radiation stress terms will be computed;
   4. (optional) key "Import_Max_Radius" to prescribe the max. (search) radius in meters during import of data (interpolation of water level as

      well as current velocity onto the grid of the wave model); if this key is not present, a radius of 2000.0 m will be used.

   5. (optional) key "Import_Min_Nearest" to prescribe the minimum number of required interpolation points during import of data; for

      every computational point of the wave model within a distance of "Import_Max_Radius" a minimum number of data points with given water

      level an current velocity must be available; if this key is not prescribed, 3 interpolation points are going to be used.

   6. (optional) key "Export_Max_Radius" to prescribe the max. (search) radius in meters during export of data (interpolation of wave model results onto the

      grid for water level as well as current velocity); if this key is not present, a radius of 2000.0 m will be used.

   7. (optional) key "Export_Min_Nearest" to prescribe the minimum number of required interpolation points during export of data; for

      every point of the computational grid for water level and current velocity (e.g. computational grid of a coupled hydrodynamic numerical model)

      within a distance of "Export_Max_Radius" a minimum number of data points with wave model results must be available; if this key is not

      prescribed, 3 interpolation points are going to be used.

   8. (optional) Key "Export_Only_Loc_Ip" defines that points of the computational grid for water level and current velocity can lie outside of "Export_Max_Radius" and are then not assigned a value.
6. block Wave_Discretisation gives the discretisation of the wave spectrum:
   1. key "Nof_Wave_Numbers" prescribes the number of discrete wave numbers or frequencies used;
   2. key "Nof_Wave_Directions" prescribes the number of discrete wave directions used;
   3. key "Lowest_Wave_Number" determines the smallest wave number of the discrete spectrum.
7. block Output_Times_And_Timesteps contains different informations relatated to output of computed results in different BAW- as well as GKSS-specific formats:
   1. key "Intrinsic_Data_Timestep" gives the time steps for data output in GKSS-specific formats; the results are stored in
      1. MAPYYYYMMDDhhmmss (integral wave data) and
      2. OUTYYYYMMDDhhmmss (spectral wave data).
   2. key "Integrated_Data_Output" prescribes initial date and time, final date and time as well as the time step to store integral wave data in BAW-specific data formats.
   3. key "Integrated_Data_Output_Nc" prescribes initial date and time, final date and time as well as the time step to store integral wave data for a NetCDF using UGRID CF metadata.
   4. key "Spectral_Data_Output" prescribes initial date and time, final date and time as well as the time step to store wave spectra in a NetCDF file using BAW specific metadata.
   5. key "Spectral_Data_Output_Nc" prescribes initial date and time, final date and time as well as the time step to store wave spectra in a NetCDF file using NODC CF metadata.
8. block Output_Files with names and types for the different BAW-specific data files:
   1. key "Integrated_Data_File" contains the file name as well as the file type (BDF) to store integral wave parameters (filetypes dirz.bin.r, dirz.bin.i and dirz.bin).
   2. key "Integrated_Data_File_Nc" contains the file name as well as the file type (NetCDF) to store integral wave parameters in UGRID- and CF-compliant NetCDF files.
   3. key "Spectral_Data_File" contains the file name as well as the file type (NETCDF) to store spectral wave data (filetype netcdf.cdf).
   4. key "Spectral_Data_File_Nc" contains the file name as well as the file type (NETCDF) to store spectral wave data in NODC- and CF-compliant NetCDF files.
9. block Output_Data for steering the amount of data output:
   1. key "Wave_Data" to switch on or off output of wave data;
   2. key "Sea_Data" to switch on or off output of sea data;
   3. key "Swell_Data" to switch on or off output of swell data.
10. block Open_Boundary_Data with auxilary informations to compute the wave spectrum along open model boundaries:
    1. key "Fetch_Length" with different wind wave direction dependent fetch lengths (in km) which will be used to determine the boundary spectrum.
11. block Area_To_Be_Printed with geometric informations concerning the printer output of results within a tile of the computational domain:
    1. Key "First_X": coordinate for the left boundary;
    2. Key "Last_X": coordinate for the right boundary;
    3. Key "First_Y": coordinate for the bottom boundary;
    4. Key Key "Last_Y": coordinate for the top boundary;
    5. Key "X_Increment": grid size in x-direction;
    6. Key "Y_Increment": grid size in y-direction
12. (optional) block Input_Files with several additional input files:
    1. (optional) key "Specific_Locations" : Name of a file of the type location.dat, with a list of one or more positions for the output of the spectral sea data, whereby the descriptions of the positions must be available in files of the type geopos.dat. The temporal validity of the data can be expressed in the file name for this file in accordance with ISO 8601. Example: locations_1957-04-23_GMT_P1Y.dat.
    2. (optional) key "Alternative_Grid_File" : name and type (GITTER05, UNTRIM_BAW) of a file with an alternative computational grid (filetype untrim_grid.dat or gitter05.dat/bin), on which the wave spectrum shall be computed.

Notice:

• dictionary-file k_model_dico.dat, usually present in directory $PROGHOME/dic/, will be automatically read by the application program in addition to the user-specified

input file.

Programs using this Type of File

UNK, UNTRIM, UNTRIM2, UNTRIM2007

Example-File

please refer to $PROGHOME/examples/unk/k_model.dat

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