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iMOD User Manual version 4.4 (html)


5.5iMOD Project Manager

The files needed in a model simulation are defined in the iMOD Project Manager. On the menubar click View and then choose the option iMOD Project Manager to open the corresponding window.

The iMOD Project Manager window shows a list of all possible model input topics. iMOD saves the characteristics in a project file, a so called *.PRJ file. From a project file a runfile (*.RUN) can be generated that will be used in the model simulation, see Section 7.9 or a standard MF2005 configuration can be save (*.NAM), see Section 5.5.5. Moreover, a runfile can be read and used to write a *.PRJ file. During the creation of a model configuration (*.RUN or *.NAM), it is possible to change the number of model layers and/or the time characteristics of the simulation, e.g. the begin and end time and/or sizes in stress-periods and/or the configuration of packages.

iMOD Project Manager window:

Initially:               After reading a project (*.PRJ) file:

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Note: The Project Manager does not yet support the PKS package.


Project
Definition

All acronyms bracketed are described in more detail in Chapter 10. Once a project file *.PRJ (or a runfile *.RUN) has been read, the topics that contain model information (recognized by the small “plus” signs) can be expanded to access the underlying files/information.


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Refresh
Click this button to refresh the Project Definition table. All definitions will be removed.


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Delete
Click this button to delete the selected entry. If the main category is selected, the entire category will be deleted. If a single entry is selected, the corresponding package entry will be deleted.

Question to confirm the desired removal of a category.

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Question to confirm the desired removal of a single entry.

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Question to confirm the desired removal of all entries for a selected date.

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Open Project file (*.prj)
Click this button to select a project file (*.PRJ). iMOD will read the project file and fills the treeview in the Project Definition table.


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Save Project file (*.prj)
Click this button to save the project file (*.PRJ) on disk.


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Open Runfile (*.run)
Click this button to select a runfile (*.RUN). iMOD will read the entire runfile and fills the treeview accordingly in the Project Definition table.


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Save Runfile (*.run / *.nam)
Click this button to create a runfile (*.RUN) or MF2005 configuration (*.NAM) file. It starts the Define Simulation Configuration window, see Section 5.5.5.


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Draw
Click this button to port the files within the selected topic to the iMOD Manager and to display the files. The action of the Draw button depends on the selection in the tree view. It will port all files underneath the selected branch. Whenever a branch is expanded individual files can be selected that need to be ported to the iMOD Manager.

Draw all files in the expanded branch:     Draw the selected file only:

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Packages that are defined by constant values instead of spatial datasets, such as IDF, IPF, ISG and/or GEN-files (e.g. lay=3;fct=1.0;imp=0.0;constant=15.0) will not be ported to the iMOD Manager.


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Special Open:

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In this case, the files that are assigned to the \(3\) layers will be opened in the order top elevation, transmissivity and bottom elevation for each model layer, up to the \(3^{\rm rd}\) model layer. More options are:

  • • TOP1 - BOT1 - TOP2 - ...
    Ports the IDF files for the top and bottom elevations to the iMOD Manager;

  • • TOP1 - KDW1 - BOT1 - TOP2 - KDW2 - BOT2 ...
    Ports the IDF files for the top, transmissivity and bottom elevations to the iMOD Manager;

  • • TOP1 - KDW1 - BOT1 - VCW1 - TOP2 - BOT2 - VCW2 - TOP3 ...
    Ports the IDF files for the top, transmissivity, bottom elevations and vertical resistance to the iMOD Manager;

  • • TOP1 - BOT1 - VCW1 - TOP2 - BOT2 - VCW2 - TOP3 ...
    Ports the IDF files for the top, bottom elevation and vertical resistance to the iMOD Manager;

  • • TOP1 - SHD1 - BOT1 - TOP2 - SHD2 - BOT2 ...
    Ports the IDF files for the top, starting head and bottom elevations to the iMOD Manager;

  • • TOP1 - KHV1 - BOT1 - TOP2 - KHV2 - BOT2 ...
    Ports the IDF files for the top, horizontal permeability and bottom elevations to the iMOD Manager;

  • • TOP1 - BOT1 - KVV1 - TOP2 - BOT2 - KVV2 - TOP3 ...
    Ports the IDF files for the top, bottom elevations and vertical permeability of the interbed to the iMOD Manager;


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Define Characteristics:
Click this button to open the Define Characteristics window, see Section 5.5.1.


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Define Characteristics Automatically:
Click this button to open the Define Characteristics Automatically window, see Section 5.5.3.2.


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Calculator
Click this button to start the Predefined Calculations window in which it is possible to complete standard calculations on model parameters, such as computed vertical resistances between model layers based upon permeability values and top- and bottom of model interfaces.

Predefined Calculations:

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The following predefined calculations are implemented:

  • Transmissivities
    Based upon the horizontal permeability (m/d) values per modellayer and the top- and bottom of model layers, the transmissivity (m\(^2\)/d) is computed;

  • Vertical Resistances Aquitards
    Based upon the vertical permeability (m/d) in between model layers, the vertical resistance (d) of the intermediate model layer (aquitard) is computed;

  • Total Vertical Resistances
    Based upon the horizontal permeability (m/d), the top- and bottom, the vertical anisotropy (-) per model layer and the vertical permeability (m/d) in between model layers, the total vertical resistance (d) between model layers is computed.

The computation can be carried out for the total modeling domain or for the current zoom window of the graphical canvas. Also, it can be done for a selected (sub)set of model layers.

Help ...

Click this button to start the iMOD Help Functionality.

Close

Click this button to close the iMOD Project Manager.

Note: For transient (time variant) topics, individual stressperiods (specific dates and/or periods) can be assigned to packages as a whole. They become accessible in the iMOD Project Manager. Those (and time invariant topics) may contain more than one levels (subtopics) of necessary input, such as ANISOTROPY that consists of FACTORS and ANGLES and DRAINAGE that consists of CONDUCTANCE and DRAINAGELEVEL. Use the Define Characteristics Automatically button (  pictures/h1-h3/properties_auto.png ) option to efficiently configure the time variant model input and/or multi-layered input.

Anisotropy with more subtopics:     Drainage/Constant Head with time variant information:

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5.5.1Define Characteristics

The Define Characteristics pictures/h1-h3/image192.png ) option of the iMOD Project Manager window opens a window which enables to define the characteristics of the model input topics as described below. Note: Whenever the PST package is selected a dedicated window is displayed (see Section 5.5.2).

Define Characteristics window:

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Package is ACTIVE for coming simulations, deselect to Deactivate Parameter

Check this option to exclude, in case it is ACTIVE, or include, in case it is DEACTIVE (red bar), this model topic when saving a runfile (*.RUN).

Steady-state

Check this button to define a steady state model input for the selected topic.

Transient, start from

Check this button to define input for use in a transient model. Enter the start date for the input in the input fields to the right. Besides defining the date there is also the option of defining the time [hh]:[mm]:[ss]. E.g. entering \(10^{\rm th}\) of June 2014 08 00 00 means that the input files as specified under Parameter Assignment: are starting at the \(10^{\rm th}\) of June 2014 at 08:00:00 am forward. The packages end, whenever another input is defined ahead of time.

Transient period:

Select a predefined period to indicate the start period for the current topic. This period will be endless in time, unless another input is defined ahead in time.

Define Periods...

Click this button to open the window in which it is possible to add and/or alter period definitions, see Section 5.5.4.

Assign parameter to
model layer …

Enter the model layer number to which the input is assigned in the model. Three options are possible:

  • • Layer = 0 (for time variant input)
    A zero-value will assign the characteristics automatically to the model layers intersected by the depth of the model topic (e.g. the depth of the screen for wells or the depth of stage to bottom level for rivers);

  • • Layer < 0 (for time variant input)
    A negative value will assign the characteristics to the upper most active model layer as defined in the Boundary Condition. Whenever the RCH and/or EVT packages are selected, the appropriate flags in the corresponding MF2005 packages will be set to 3 to indicate this automatic layer assignment;

  • • Layer > 0
    A positive value will assign the characteristics to the corresponding model layer.

Parameter:

Choose the parameter for which the Parameter Assignment will be defined. Depending on the model input topic the number of parameters is 1 (e.g. for WEL), 2 (e.g. for ANI), 3 (e.g. for EVT) or 4 (e.g. for RIV). See Chapter 10 for detailed information about these different input per topic.

Extra files:

Click this option to add extra files to the topic. This option is only available whenever the MSW (Unsaturated Zone) package is selected.

Extra Files:

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In this case, the files are listed to be copied in a simulation with MetaSWAP.

Inherent from previous definition:

Select this option to inherent the input for the selected topic from the previous (in time) definition for this topic.

Assign Parameter
Multiplication Factor:

Change the multiplication factor from the default value 1.0 in case the model input needs to be multiplied. Multiplication goes before the additional value.

Assign Parameter
Addition Value:

Change the addition factor from the default value 0.0 in case the model input needs to be increased (added) with a constant value. Multiplication goes before the additional value.

Add constant value

Check this button and enter a constant value for the parameter for the whole model area.

Add file:

Check this option and enter a file name to be used for the parameter. It depends on the package whether an IDF, IPF, ISG or GEN file need to be entered.


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Open File
Click this button to open the a Windows Explorer to locate the file name for the parameter, this can be an IDF, IPF, ISG or GEN file that depends on the topic considered.


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Open
Click this button to select a folder, remember to add a wild-card to the folder name in order to select appropriate file names by iMOD.

Help ...

Click this button to start the iMOD Help Functionality.

Add System
Adjust System

Check this button to save the entered input for the selected topic and return to the Project Manager window. This can mean that the parameter for an existing topic are adjusted, or a new system is added to a topic. The tree-view in this window will collapse all topics and expand the selected and modified topic. For large project configurations with many time-definitions it can take several minutes to (re)fill in the tree-view field.

Note: Packages are assigned to a particular date and time at which they start. They will never end, but can be overruled by another packages that is defined ahead of them. In the following figure it is explained what this means whenever more packages become available and interact whenever periods are defined.

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In the figure shown above, a) describes the situation in which only a single package T\(_1\) is defined half-way a simulation between Start and End. In b), another package T\(_2\) is defined and overrules T\(_1\) at the start of T\(_2\). In c), a third package T\(_3\) is defined before T\(_1\) and even before the start of the simulation. Consequently, the package T\(_3\) becomes active, directly at the start of the simulation. In d), a period P\(_1\) and P\(_2\) are defined at a certain moment within a single year, they will be repeated for each year, automatically. Finally, in e) a package T\(_4\) is defined besides the period definitions P\(_1\) and P\(_2\). As a consequence, the package T\(_4\) will split period P\(_1\) halfway, up to the moment period P\(_2\) is defined again.


5.5.2Parameter Estimation

Parameter Estimation Settings window:

Within the Parameter Estimation Settings window it is possible to configure the settings for a parameter estimation. Several options are available, such as defining the main settings, the number and characteristics of parameters, the zones and measurements, see section Section 12.33 for more detailed information on parameter estimation. Most of the parameters are described in more detail in section Section 10.14 as well.

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Apply Parrallel iPEST

Select this option to use parrallel iPEST. In this case iMOD will steer the optimization and start all simulations that are needed for the sensitivity computations. Whenever this option is unchecked, iMODFLOW is steering the optimization.

Hide Command Windows
Select this option to hide the command-windows in which the individual model run. This is strongly recommended as (re)starting of all individual models disturb usage of the computer for other activities. Uncheck this option in the case individual sub models won’t run and it is needed to inspect any errors.

Number of Processors:
Enter the number of processors that is available at the current computer. The entered number determines the number of individual models that start in parallel.

Maximum Number of Sequences

Enter the number of sequences (iteration) of the parameter estimation routine. Enter a zero will start a sensitivity analysis only.

Stop Criterion Reduction of Objective Function

Enter a percentage for which the objective function needs to be reduced between adjacent iteration in order to terminate the parameter estimation process. The percentage is computed as the ratio between the previous and current objective function value.

Stop Criterion Parameter Adjustment

Enter a value for this stop criterion between 0.0 and 1.0 to terminate the parameter estimation whenever it becomes less than the specified value. The stop criterion is computed as

Ignore parameter with maximal Sensitivity

Enter a percentage of the sensitivity of a parameter which will be excluded from the current parameter estimation cycle, whenever its sensitivity is less than the specified value.

Minimal Acceptable Residual

Enter a value to skip measurements in the formulation of the objectie function whenever the absolute residual is less than the specified value.

Enter a fraction for each Target

Enter a weight value for two targets of the objective function; the first target is the sum of the square root residuals, the second the sum of the square root residual of the dynamic in a measurement (see Section 12.33.1). Its is not necessary to scale them to a sum of 1.0, internally the entered fraction will be scaled to a total sum of 1.0, this includes any Batchfiles included (see NUmber of Batchfiles further below).

Specify Scaling / SVD

Scaling can be used whenever parameters yield significant different sensitivities; SVD (Eigenvalue Decomposition) is a process in which parameters can be grouped mathematically of excluded/ignored in the parameter optimization. This can be done manually (using the parameter sensitivity) or automatically by means of some mathematically expressions. It is encouraged to apply SVD at all times. Select of the following options:

  • No Scaling / SVD
    No use of scaling and/or SVD;

  • Scaling
    Use Scaling, use this option whenever the amplitude of different residuals differ significantly, such as measurements of groundwater level and discharge;

  • Scaling and SVD
    Use Scaling and Eigenvalue Decomposition whenever it is very difficult to exclude parameters on their sensitivity or relevant contribution to the reduction of the objective function;

  • Eigenvalues
    Use Eigenvalue Decomposition whenever the parameter sensitivity alone, is not enough the estimate the relevance of a parameter to the parameter optimization.

Tikhonov Regulariation

This type of regularisation allows to include the modification of parameters in the penalty function (objective function). Large modifications are punished more than less modifications. It is advised to include this type of regularisation as it avoid parameters to differ too much from their posterior estimate.

Variable Weighting
As the misfit between measurements and computed heads can be weighted, so is the difference between the posterior estimate and the estimated values. The values of 1.0 indicates that a change in variables is penalised similar as a misfit between the measurements. If many measurements are included, the penalty of the estimated values need to be in magnitude with the reduction of the objective function. In the end the objective function value with and without the Tiknonov Regularation is printed in the log files, based on this, the size of the Variable Weighting can be estimated more realistically.

Kriging Type

Specify the type of Kriging (Section 12.33.3.1) whenever the Pilot Point concept is used (Section 12.33.3). Whether Pilot Points are used is steered by the fact that an IPF file will be entered by the zones (see Number of Zones) instead of IDF files. The following options are available:

  • Simple Kriging (Section 12.33.3.1)
    Simple Kriging assumes stationarity of the mean, all variables have the same mean over the entire domain;

  • Ordinary Kriging (Section 12.33.3.1)
    In Ordinary Kriging a unknown mean is assumed only over the search neighborhood, so the mean is recomputed for the values in the search neighborhood.

Define Periods ...

Click this button to define periods (see Section 10.15) for which measurement need to be included in the computation of the objective function, e.g. \(1^{\rm st}\) of January 2010 to the \(31^{\rm st}\) of December 2010 and the \(1^{\rm st}\) of January 2012 to the \(31^{\rm st}\) of December 2012.

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Click the Define Periods to increase or decrease the number of available rows (entry fields) in the table, e.g. \(2\). There is a maximum of \(10\) rows. Click the Apply button to accept your entry, click the Cancel to ignore any changes, click the Help button to start the Help-functionality.

Define Batchfiles ...

Click this button to define batchfiles (see section Section 10.16) for which extra or additional measurement need to be included in the computation of the objective function.

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Click the Define Batchfiles to increase or decrease the number of available rows (entry fields) in the table, e.g. \(1\). There is a maximum of \(10\) rows. Click the Apply button to accept your entry, click the Cancel to ignore any changes, click the Help button to start the Help-functionality.

Define Parameters ...

Click this button to define parameter to be optimized.

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Click the Define Parameters to increase or decrease the number of available rows (entry fields) in the table, e.g. \(2\). There is a maximum of \(1000\) parameters, see section Section 10.17 for the explanation of the variables. Click the Apply button to accept your entry, click the Cancel to ignore any changes, click the Help button to start the Help-functionality.

Define Zones ...

Click this button to define zones (see section Section 10.19) for which parameters need to be adjusted.

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Click the Define Zones to increase or decrease the number of available rows (entry fields) in the table, e.g. \(5\). There is a maximum of \(1000\) zones, constant values can be entered to denote a zone fore the entire model area, multiply zones can be combined in a single IDF file and/or IPF files can be entered for usage of Pilot Points (Section 12.33.3). Click the Apply button to accept your entry, click the Cancel to ignore any changes, click the Help button to start the Help-functionality.

Define Measurements ...

Click this button to define measurements (see section Section 10.4) which are needed to compute the objective function. It is also possible to exclusively use Batchfiles instead.

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Click the Define Measurements to increase or decrease the number of available rows (entry fields) in the table, e.g. \(2\). There is a maximum of \(50\) zones, constant values can be entered to denote a zone fore the entire model area, multiply zones can be combined in a single IDF file and/or IPF files can be entered for usage of Pilot Points (Section 12.33.3). Click the Apply button to accept your entry, click the Cancel to ignore any changes, click the Help button to start the Help-functionality.

Apply System Settings

Click this button to leave the Parameter Estimation Settings window and store the adjustments.

Cancel

Click this button to close the Parameter Estimation Settings window

Help ...

Click this button to start the Help-functionality


5.5.3Define Characteristics Automatically

The Define Characteristics Automatically pictures/h1-h3/properties_auto.png ) option on the iMOD Project Manager window opens a window which enables to define the characteristics of the model input topics in a more advanced way than the default Define Characteristics window (see Section 5.5.1). The process consists out of two steps. In the first step you define the characteristic of the source for each topic, in the second step iMOD will list the found sources and it is possible to modify this list manually before adding them to the Project Manager window.


5.5.3.1Define Source for Topics

The first step is to define the type of sources for each topic.

Define Characteristics for: window

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Define Package

This table show how each of the topics for the package (here the topics CON, RST, RBT and RIF for the RIV package) need to be specified. Three options are available

  • • Constant Value
    Specify a constant value for the topic to be used for all stress-periods or model layers, e.g. a value of 90.0 means that this topics is 90.0 for all stress-periods or model layers;

  • • File Name
    Specify a file name for the topic to be used for all stress-periods or model layers, e.g. a file name as D:\MODEL\DBASE\BOTTOM.IDF applies that this file is used for all stress-periods or model layers;

  • • Wild card
    Specify a file name with a wild card ( * ) to specify that all files that are part of this will be added. It depends whether a module or package is associated, for modules layers can be added this way, for packages multiple stress periods, e.g. D:\MODEL\DBASE\STAGE_*_.IDF will add all files that belong to this group.

iMOD will look for unique TIMESTEPS

Select this option to select unique timesteps and add the related files to your project.

iMOD will look for unique LAYERS

Select this option to only select unique layers and add the related files to your project.

Select files within given layer range

Select this option to be able to only select the files of the given layer range of your project.

Select files within given time frame only

Select this option to define the start- and end date for the input. Besides defining the date there is also the option of defining the time [hh]:[mm]:[ss]. E.g. entering \(10^{\rm th}\) of June 2014 08 00 00 means that the input files as selected at the \(10^{\rm th}\) of June 2014 at 08:00:00 am up to the specified end date.

Allocate Files ...

Click this button to apply the given sources for topics and pop-up a list of constant values and/or file namer per model layer or stress period.

Help ...

Click this button to start the iMOD Help Functionality.

Cancel ...

Click this button to close the Define Characteristics Automatically window and return to the Project Manager window.


5.5.3.2Modify List of Topics

The second step is to inspect the list of found files based on the given sources for each topic.

Define Characteristics for window:

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5.5.4Define Periods

A period is defined by a starting date and time for which a package, assigned to that period, will be repeatedly included in the runfile. A period start at a particular moment in time, but it will never end repeating itself. The only way of ending a package defined by a period, is by defining another package after or equal to the starting date of the period.

Define Periods window:

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New
Click this button to define a new period. In the following window it is possible to enter a name for the period.

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Use the OK button to agree with the entered period name, click the Cancel button to cancel the creation of a new period. Click Help to open the iMOD help functionality.


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Rename
Click this button to rename an existing period name. Usage of the window as described by New will be used.


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Delete
Click this button to delete the selected period. Whenever the last period is delete, iMOD will ask to enter a period name as described by New and if this cancelled, the Define Period window will be closed.

Summer

Select one of the predefined period from the dropdown list. If none available, create one first by means of the New button.

From

Modify the starting date and time for the selected predefined period. In this example the period Summer is a period starting from 1990 and thereafter each year at the \(1^{\rm st}\) of April at 08:00:00 am. Any modification will effect any systems for topics that are assigned to that period definition.

Help ...

Click this button to start the iMOD Help Functionality.

Apply

Click this button to close this window, any modification to a period definition will be stored.


5.5.5Define Simulation

Define Simulation window:

Within the Define Simulation window it is possible to configure the runfile and/or standard Modflow2005 configuration files. Several options are available, such as defining the location and size of clip models, time-discretisations and active packages.

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Full Extent

iMOD choses the extent of the first IDF mentioned in the PRJ file, often the TOP, BOT or Boundary file.

Window

Check this option to define the lower- and upper-right-corner, buffersize and cellsize of a submodel or clipmodel to be included in the runfile or used to generate the Modflow2005 configuration files.

Network IDF

This option gives you the option to upload an IDF file with the (non) equidistant cell size you prefer.

Transient

Check this option to generate a transient runfile (*.RUN) or Modflow2005 configuration files. iMOD will collect all packages that are within the specified Start Date and End Date. Besides defining the date there is also the option of defining the time [hh]:[mm]:[ss]. On default the start- and end time is set to 00:00:00.

Start Date

Enter a start date and time for the transient simulation, this date will be start of the first stress-period. iMOD will fill in this Start Date initially with the earliest defined date in the packages. Whenever the Start Date is decreased, before the initial value, the model will include packages that remain inactive until the first dat at which they are defined.

End Date

Enter an end date and time for the transient simulation, this date will be the end of last stress-period. iMOD will fill in this End Date initially with the latest defined date in the packages. The End Date is the date at which the simulate will terminate, so it is the end of the last stress period. It is allowed to increase the End Date beyond the initial value to enforce the latest stress period to be include in the model.

Steady-State

Check this option to generate a runfile (*.RUN) for a steady-simulation, the option becomes available only whenever at least one package is defined for a steady-state period. iMOD will collect all packages that are connected to a steady-state definition as specified in the Define Characteristics window.

Include
Steady State
period

Select this option to include an initial steady-state period, prior to the start of the transient simulation. This option becomes available whenever at least one package is defined for a steady-state period, see section Section 5.5.1.

TimeSteps

Select one of the option from the drop down menu:

  • Minutes
    Select this option to generate minute stress-periods;

  • Hourly
    Select this option to generate hourly stress-periods;

  • Daily
    Select this option to generate daily stress-periods;

  • Weekly
    Select this option to generate weekly stress-periods;

  • 14/28
    Select this option to generate stress-periods on the 14th and 28th day of each month;

  • Monthly
    Select this option to generate monthly stress-periods;

  • Yearly
    Select this option to generate yearly stress-periods;

  • Decade
    Select this option to generate stress-periods per decade;

  • Packages
    Select this option to generate stress-periods that are determined by the input data as specified by the available packages in the Define Characteristics window. It can yield a non-constant time sequence for stress periods, but will be most optimally to the amount of stress-periods;

  • Custom
    Select this option to refine or inspect time configuration priorly defined. This option is selected automatically after the first time the option Customize is selected.

Customize...

Click this button open the Time Discretization Manager for Simulation window to customize the time steps of the simulation to be included in the runfile and/or Modflow2005 configuration.

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  • Select
    Enter the row number within the table to be modified, e.g. \(9\) ad \(11\), those will be displayed by a red box to indicate the selected rows;

  • Time Steps
    Select this option to modify time steps in the table;

  • Save Intervals
    Select this option to modify the save intervals in the table;

  • Modify Time Steps / Modify Save Intervals
    Click the button to adjust the selected rows according to the selected settings in the fields right of this button and explained below;

  • 1
    Enter a number to enter time steps sizes for the selected value from the drop down menu, next to it to the right, e.g. \(1\) means in this case \(1\) day.

  • Daily
    Select from the drop down menu the appropriate time step size to be used for the selected rows. E.g. Daily will include time steps on a daily base for the selected rows. Other choices are Minutes, Hourly, Weekly, Monthly, Decade, 14 / 28, Yearly, Packages

  • Off / On
    Select on of the options to turn the Save interval for the selected rows on or off;

  • Save As
    Click this button to save the current time step configuration to a *.TIM file, see Section 9.4;

  • Open
    Click this button to load the current time step configuration from a *.TIM file, see Section 9.4;

Packages ...

Click this button to select the Number of Layers and to define the Type of Layers.

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By default all packages are selected, those are listed on the uppermost right corner on the Define Simulation window as well. Use the CTRL-left-mouse button to selected and deselect packages. It is not recommended to deselect packages that are essential for a correct simulation of the model, such as the BND, SHD packages. Click the Apply button to accept your choice, click the Cancel to leave the Packages window without any changes in the selected package and click the Help button to start the Help-functionality.

Define 3
Layer
Types ...

Click this button to select the packages that need to be active in de model.

pictures/h1-h3/layer_types.png

  • Number of Modellayers
    Enter a number of modellayers for which the model configuration need be built and click on the button Adjust.
    iMOD will fill in the maximum number of modellayers based on the modellayers that have been filled in for the most important packages, BND, SHD (TOP and BOT), KDW or KHV and VCW or KVV.

  • Type
    Select on of the 4 available layer types: Confined (TOP-BOT), Convertible (HNEW-BOT), Convertible (SHD-BOT) or Constant Head.

File
Format:

The file format of the model configuration can be defined with this option. There are two possibilities:
iMOD Runfile and/or standard MODFLOW2005 files.

iMOD
Runfile,
name of
the output:

Select this option if the iMOD Runfile format is preferred. Give the name of result folder to be created by the runfile, e.g. the result folder is finally located in the {USER}\MODELS \MODEL. After selecting the OK button, it is necessary to enter the name of the runfile to be created.

MODFLOW 2005

Select this option if the MODFLOW 2005 format is preferred. After selecting the OK button, it is necessary to enter the name of the namfile to be created.

Subsoil package

Select one of the configuration options to denote the subsoil characteristics in the Modflow2005 files (BCF or LPF). The availability of the options depend on the active packages.

Usage of
confining beds

Select the No Confining bed whenever the model configuration is 3-D, that is there are no confined beds, the bottom of each model layer is equal to the top of the underlying model layer. Select the Confining Bed whenever the bottom of each or at least a single model layer is not equal to the top of the underlying model layer.

Storage Definition

...

Minimal Layer Thickness (m)

Enter a minimal thickness for model layers. For Modflow2005 it is important that the thickness of model layers is not zero. Whenever a minimal thickness of \(0.01\) is entered, the top- and bottom elevations will be adapted such that there is a minimal thickness of \(0.01\) meter. Moreover, the hydraulic properties will be adjusted for those areas to reflect the corresponding layer, that will be part of the model layers that increase in thickness. Inheritance ...

Output Precision

Choose for creating the Modflow files with Single (default) or Double precision. Bear in mind that all files will be doubled in size as well as the option for double precision is selected. Also, result files saved in double precision cannot be read in iMOD versions older than version 4.3.

Create ...

Click this button to select an existing or non-existing runfile (iMODFLOW) and/or namfile (Modflow2005), by default iMOD will save the runfile and/or namfile in the {USER}\RUNFILES folder. It is convenient to do that as well, however not obliged, but it will allows iMOD to start the runfile from the Model Simulation tool, see Section 7.9.

Simulate ...

This option is only available in combination with the option to export files in MODFLOW 2005 format providing the option to run the model right away after finishing the creation of MODFLOW files.

Help ...

Click this button to start the iMOD Help Functionality.

Cancel

Click this button to close this window.