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iMOD User Manual version 5.2 (html)


8.7MODEL-FUNCTIONS


8.7.1IMPORTMODFLOW-Function

Use this function to import an existing MODFLOW configuration into iMOD files (e.g. IDFs, IPFs and GENs), see for more information section 9.7.

FUNCTION=

IMPORTMODFLOW

MVERSION=

Enter the version number of the MODFLOW configuration files, e.g. MVERSION=1988. There are four available versions supported: 1988, 1996, 2000 and 2005.

BASFILE=

Enter the location of the, so called, BAS file (use this keyword whenever MVERSION=1988), e.g. BASFILE=D:\MODEL\MODEL.BAS.

NAMFILE=

Enter the location of the, so called, NAM file (use this keyword whenever MVERSION=1988, 1996, 2000 or 2005), e.g. NAMFILE=D:\MODEL\MODEL.NAM.

OUTDIR=

Enter the folder in which all iMOD files will be saved, e.g. OUTDIR =D:\IMPORT. Subfolders will be created automatically to save the individual files, e.g. D:\IMPORT\BND\VERSION_1\BND_L1.IDF . By default OUTDIR =’.’ which means that the files will be saved directly at the current location of the iMOD executable.

LLCORNER=

Enter the coordinates of the lower-left corner of your model, e.g. XMIN=200000.0,YMIN=400000.0 (all in meters). By default XMIN=YMIN=0.0.

SDATE=

Enter the starting date of your simulation, e.g. SDATE=20111027 which means 27\({}^{th}\) of October 2011. By default SDATE=20110101.

PACKAGESUM=

Enter PACKAGESUM=1 to sum all existing package information into a single modelcell, this is the default. Whenever more elements occur in a single modelcell, they will be lumped together to form one value. Enter PACKAGESUM=0 to extract all elements in a single modelcell to store them, if necessary, in individual iMOD files.

RIV5TH=

Enter RIV5TH=1 to include a 5\({}^{th}\) column in the river files that expresses the infiltration resistance. On default RIV5TH=0.

Example 1

FUNCTION=IMPORTMODFLOW
MVERSION=1988
BASFILE=D:\IMOD-MODEL\VELUWE\MS1L5.BAS

This is the shortest version to import the MODFLOW model MS1L5.

Example 2

FUNCTION=IMPORTMODFLOW
MVERSION=2005
NAMFILE=D:\MODEL\GWR54\MODFLOW.NAM
LLCORNER=125000.0,432000.0
SDATE=20050101
PACKAGESUM=0
RIV5TH=1

This example shows how to import a (transient) MODFLOW2005 configuration.


8.7.2IMPORTSOBEK-Function

Use this function to import a SOBEK configuration into ISG-files for iMOD, see for more information section section 9.9.

Note: This function is only available in the X64-bits version of iMOD. The resulting ISG will be written in a double-precision format by default.

FUNCTION=

IMPORTSOBEK

ISGNAME=

Enter the name of the ISG-file to be created, e.g. ISGNAME=D:\IMPORT\SOBEK.ISG.

SOBEKDIR=

Enter the name (location) of the SOBEK files, e.g. SOBEKDIR=D:\DATA. iMOD will search for all other files that it need in the folder D:\DATA, these files are:

  • • {SOBEKDIR}\NETWORK.TP

  • • {SOBEKDIR}\NETWORK.CR

  • • {SOBEKDIR}\NETWORK.CP

  • • {SOBEKDIR}\NETWORK.GR

  • • {SOBEKDIR}\NETWORK.ST

  • • {SOBEKDIR}\PROFILE.DAT

  • • {SOBEKDIR}\PROFILE.DEF

  • • {SOBEKDIR}\PROFILE.DEF

  • • {SOBEKDIR}\FRICTION.DAT

CALCHIS=

Enter the name of the HIS file that contains the computed waterlevels at the calculation points, e.g. CALCHIS=D:\SOBEK\CALC.HIS.

STRUCHIS=

Enter the name of the HIS file that contains the computed waterlevels at the structures, e.g. STRUCHIS =D:\SOBEK\STRUCT.HIS.

DFLOWFMDIR =

Enter the name of the directory of a DFLOWFM model to import DFLOWFM model networks and schematisation into an ISG file.

Example 1

FUNCTION=IMPORTSOBEK
ISGNAME=D:\IMPORT\HCMC0611.ISG
SOBEKDIR=D:\SOBEK\HCMC0611
CALCHIS=D:\SOBEK\HCMC0611\CALCPNT.HIS
STRUCHIS=D:\SOBEK\HCMC0611\STRUC.HIS

The above mentioned examples imports the SOBEK model (files) in the folder D:\SOBEK\HCM0611\* and combines this with the computed results from the two entered HIS files (CALCPNT.HIS and STRUC.HIS) and saves it in HCMC0611.ISG.


8.7.3MODELCOPY-Function

The function MODELCOPY can be used to extract a separate data set for a sub model from a large model. It can also be applied to copy the entire dataset as specified by the entered RUNFILE or PRJFILE into a separate folder. In this process, all IDF and IPF files that can be identified in a given RUNFILE or PRJFILE, will be clipped to the given window. Other files that are mentioned in the RUNFILE or PRJFILE will be copied. As a result a complete copy of a part of the original model will be saved and can be simulated separately.

Note: Other files that might be referred to from files other than the specified runfile, will not be copied.

FUNCTION=

MODELCOPY

RUNFILE=

Enter the name of a runfile that contains a specific set of IDF-file(s), e.g. RUNFILE=D:\RUNFILES\MODEL.RUN or a PRJFILE such as RUNFILE=D:\RUNFILES\MODEL.PRJ.

TARGETDIR=

Enter the name of a folder in which the resulting files will be copied, e.g. TARGETDIR=D:\SUBMODEL.

WINDOW=
(optional)

Specify a window (X1,Y1,X2,Y2) for which the entered RUNFILE will be clipped, WINDOW=125100.0,345000.0,135000.0,355000.0. By absence of this keyword, all files will be copied as-is.

CELL_SIZE=

Specify a cellsize whenever the keyword WINDOW is specified, e.g. CELL_SIZE=250.0.

CLIPDIR=
(optional)

Enter a foldername for which all filenames will be trimmed, e.g. CLIPDIR=D:\MODEL. If the original filenames are D:\MODEL\DRN\SYS1\DRN_EL_L1.IDF and D:\MODEL\DRN\SYS2\DRN_EL_L1.IDF, they will be saved in {TARGETDIR}\DRN\SYS1\DRN_EL_L1.IDF and {TARGETDIR}\DRN\SYS2\DRN_EL_L1.IDF, respectively. By omitting CLIPDIR, both files will be stored in {TARGETDIR}\DRN\DRN_EL_L1.IDF instead.

Example 1

FUNCTION=MODELCOPY
RUNFILE=D:\RUNFILES\MODEL.RUN
TARGETDIR=D:\MODEL\SUBMODEL

The above mentioned example copies all IDF and IPF files from the runfile D:\RUNFILES\MODEL.RUN and the result is saved in D:\MODEL\SUBMODEL. A new runfile is created that will be saved in D:\MODEL\SUBMODEL\MODEL.RUN. Use this configuration to create a cleaned up folder structure of the model.

Example 2

FUNCTION=MODELCOPY
RUNFILE=D:\PRJFILES\MODEL.PRJ
TARGETDIR=D:\MODEL\SUBMODEL
WINDOW=147000.0 448000.0 155000.0 452000.0
CLIPDIR=D:\MODEL

The above mentioned example is equal to example 1 except that it clips all IDF and IPF files from the PRJFILE D:\PRJFILES\MODEL.PRJ to the window 147000.0 448000.0 155000.0 452000.0 and the files remain their original file name under D:\MODEL. In this way complex structured in file name will be preserved.


8.7.4CREATESUBMODEL-Function

Use this function to create submodels for iMODFLOW based on a pointer IDF that determines the active area to be simulated.

FUNCTION=

CREATESUBMODEL

DSIZE=

Enter the maximum size of a submodel in meters, e.g. DSIZE=10000.0.

CSIZE=

Enter the cellsize to be used in the submodels, this will be used to fill in the appropriate column in the runfile, e.g. CSIZE=25.

IBOUND=

Enter the IDF-file that describes the location of active area to be simulated, e.g. IBOUND=D:\IBOUND_L1.IDF.

SUBMODELFILE=

Enter the name of the text file that will be created that stores the header of a runfile that describes the submodels, e.g. SUBMODELFILE=D:\SUBMODELS. iMOD will create a SUBMODELFILE.RUN to be used in a runfile and a SUBMODELFILE.GEN of the submodels to be displayed in iMOD.

Example 1

FUNCTION=CREATESUBMODEL
DSIZE=10000.0
CSIZE=25.0
IBOUND=D:\DBASE\IBOUND_L1.IDF
SUBMODELFILE=D:\RUNFILE\SUBMODEL

The example above will create submodels with a maximum extent of 10000m (10km) and will write a runfile header with cellsizes of 25m. The IDF-file IBOUND.IDF will be used to determine the active areas of the model. iMOD creates boxes with 10x10km first and then decreases submodels whenever this is possible, moreover, whenever submodels become too small (25% of 10km), they will be joined together.

pictures/h6-h71/image93.png


8.7.5RUNFILE-Function

The function RUNFILE can be used to create a runfile (*.RUN) from a projectfile (*.PRJ), or create a projectfile from a runfile.


FUNCTION=


RUNFILE

RUNFILE_IN=
(optional)

Enter the name of a runfile that contains a specific set of IDF-file(s), e.g. RUNFILE=D:\RUNFILES\MODEL.RUN.

PRJFILE_OUT=
(optional)

Enter the name of a projectfile that need to be created based on the content of the runfile specified by RUNFILE_IN, e.g. PRJFILE_OUT=D:\PRJFILES\MODEL.PRJ."

PRJFILE_IN=
(optional)

Enter the name of a projectfile that need to be used to create a runfile specified by RUNFILE_OUT, e.g. PRJFILE_IN=D:\PRJFILES\MODEL.PRJ.

SIM_TYPE=
(optional)

Specify the simulation type for which the conversion needs to take place, choose from:
  • • SIM_TYPE=1: select this to export to a runfile;

  • • SIM_TYPE=2: select this to export to a standard MODFLOW2005 namfile and corresponding files;

  • • SIM_TYPE=3: select this to export to a standard MODFLOW6 namfile and corresponding files;

  • • SIM_TYPE=4: select this to export to a iMOD-WQ (Seawat) runfile;

  • • SIM_TYPE=5: select this to export to a iMOD-WQ (MT3D) runfile.

ISOLVE=
(optional)

Enter ISOLVE=1 to start a simulation after generating a RUNFILE or NAMFILE, by default ISOLVE=0.


Enter the following items whenever SIM_TYPE=1

IPKS=
(optional)

Specify IPKS=1 to apply the PKS package instead of the PCG package. The PKS seems to be more robust than the PCG solver, so you might want to use this PKLS solver in case of non-convergency due to huge contrasts in conductivities and/or using the multi-core applications. This option is applicable whenever NAMFILE_OUT is specified, whenever RUNFILE_OUT is specified, this keyword doesn’t have any effect.

MODFLOW=
(if ISOLVE=1)

Enter the simulator, e.g. MODFLOW=D:\PROGRAMS\IMODFLOW.EXE.


Enter the following items whenever SIM_TYPE=1 or SIM_TYPE=4 or SIM_TYPE=5

RUNFILE_OUT=
(optional)

Enter the name of a runfile that will be created, e.g. RUNFILE_OUT=D:\RUNFILES\MODEL.RUN.

OUTPUT_
FOLDER=
(optional)

Enter the name of an output folder that will be created to save the results of the model simulation, e.g. OUTPUT_FOLDER=D:\MODEL\OUTPUT. In the situation that RUNFILE_OUT is entered, this keyword will add the output folder at the first line of the runfile, in the situation that NAMFILE_OUT is entered, the OUTPUT_FOLDER will be written in the *.MET file.

IDEBUG=
(optional)

Enter IDEBUG=0 to generate a MF2005 compatible model, all arrays are listed in *.ARR files if needed. Use IDEBUG=1 or IDEBUG=2 to export all model input to ASC or IDF, respectively.


Enter the following items whenever SIM_TYPE=4 or SIM_TYPE=5

IMOD-WQ=
(if ISOLVE=1)

Enter the simulator, e.g. IMOD-WQ=D:\PROGRAMS\IMOD-WQ.EXE.


Enter the following items whenever SIM_TYPE=2 or SIM_TYPE=3

NAMFILE_OUT=
(optional)

Enter the name of a namfile that will be created, e.g. NAMFILE_OUT=D:\NAMFILES\MODEL.NAM.


Enter the following items whenever SIM_TYPE=3 (MF6)

MODFLOW6=
(if ISOLVE=1)

Enter the simulator, e.g. MODFLOW6=D:\PROGRAMS\MODFLOW6.EXE.

IGENMF6=
(optional)

Enter IGENMF6=1 to use a GEN file to specify the sub models and their cell sizes, by default IGENMF6=0 and no sub models are applied.

GENFNAME=
(if IGENMF=1)

Specify then name of the GEN-file for the sub models and their cell sizes, e.g. GENFNAME=D:\GENFILES\SUBMODELS.GEN


Enter the following items whenever SIM_TYPE=5 (MT3D)

NPROBS=
(optional)

Observation point output frequency (NPROBS) is an integer indicating how frequently the concentration at the specified observation points should be saved in the observation file MT3Dnnn.OBS. Concentrations are saved every NPROBS step.

NPRMAS=
(optional)

Output frequency (NPRMAS) is an integer indicating how frequently the mass budget information should be saved in the mass balance summary file MT3Dnnn.MAS. Mass budget information is saved every NPRMAS step.

MIXELM=
(optional)

Advection solution option (MIXELM) is an integer flag for the advection solution option. Choose from:
  • • -1 TVD (Total-Variation-Diminishing)

  • • 0 Finite-Difference

  • • 1 MOC (Method of Characteristics) (not available)

  • • 2 MMOC (Modified Method of Characteristics) (not available)

  • • 3 HMOC (Hybrid Method of Characteristics) (not available)

NADVFD=
(optional)

Weighting scheme Finite-difference (NADVFD) is a weighting scheme for the Finite-difference method. Choose from:
  • • 0 Upstream weighting (default);

  • • 1 Central-in-space weighting.

PERCEL=
(optional)

Courant number (PERCEL) determines the number of cells that advection is allowed to move in one transport step.

MXSS=
(optional)

Max number point sinks/sources (MXSS) is the maximum number of all point sinks and sources included in the flow model.

FLOW_RESULT_
DIR =
(optional)

Specify FLOW_RESULT_DIR to denote the folder where the results (fluxes) are saved, e.g. FLOW_RESULT_DIR=D:\MODELS\RUN1.


Enter the following items discarding SIM_TYPE

ISS=
(optional)

Specify the type of time configuration to be added to the RUNFILE or NAMFILE; for transient enter ISS=1 and for steady state enter ISS=0. By default ISS=0.
Specify following keywords for transient configurations (ISS=1)

TIMFNAME=
(optional)

Specify the name of the *.TIM file that contains the time discretisation of the model to be created, TIMFNAME=D:\RUNFILES\MODEL.TIM. For more information on the content of a *.TIM file see section 9.4.

SDATE=
(optional)

Specify a starting date of the simulation in yyyymmddhhmmss format, e.g. SDATE=20120101080000 to denote the \(1^{\rm st}\) of January 2012 at 08:00:00 am. This keyword is only compulsory whenever TIMFNAME is absent.

EDATE=
(optional)

Specify a starting date of the simulation in yyyymmddhhmmss format, e.g. EDATE=20121231153030 to denote the \(31^{\rm st}\) of December 2012 at 15:30:30. This keyword is only compulsory whenever TIMFNAME is absent.

ITT=
(optional)

Specify a time interval category, e.g. ITT=2 to denote days. The other are:

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

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

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

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

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

  • 6 14/28
    Select this option to generate stress-periods on the 14th and 28th day of each month;

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

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

  • 9 Packages
    Select this option to generate stress-periods that are determined by the input data

This keyword is only compulsory whenever TIMFNAME is absent.

IDT=
(optional)

Specify a time interval of the time steps corresponding to the chosen time interval category ITT, e.g. IDT=7 to denote the \(7\) days whenever ITT=2. This keyword is only compulsory whenever TIMFNAME is absent.

ISTEADY=
(optional)

Specify ISTEADY=1 to include an initial steady-state time step to the model. This will add packages with the time stamp STEADY-STATE to the first stress-period of your model. By default ISTEADY=0.

NSTEP=
(optional)

Specify the number time step within each stress period, e.g. NSTEP=10. Whenever a model suffers some convergence issues, increase the number of time steps might help. Also, steady-state convergence problems can be overcome by creating a transient model with enough time step. By default NSTEP=1.

NMULT=
(optional)

Specify the multiplication factor in which the step size of each subsequent time step will increase, e.g. NMULT=1.2. The factor need to \(\ge \) 1.0. The higher the number to more explosive the size will increase in subsequent time steps according to:

\begin{equation} \Delta t_i= \Delta T_j \left ( \frac {{\rm NMULT}-1}{{\rm NMULT}^{\rm NSTP}-1} \right ) \end{equation}

wherein \(\Delta _i\) is the current length of the time step \(i\), \(\Delta T_j\) is the total length of the current stress period \(j\). By default NMULT=1.0.

SSYSTEM=
(optional)

Specify SSYSTEM=1 to SUM each SYSTEM for a package into a single file. By default SSYSTEM=0 and each system yields a separate output file including a system number in the given output name.

ISAVEEND
DATE=
(optional)

Specify ISAVEENDDATE=1 to save each file with a time stamp equal to the end of the corresponding stress period (and/or time step). By default ISAVEENDDATE=0 and the time stamp will be equal to the start date of each stress period (and/or time step). This option is applicable whenever NAMFILE_OUT is specified, whenever RUNFILE_OUT is specified, this keyword doesn’t have any effect.

ICHKCHD=
(optional)

Specify ICHKCHD=1 to convert constant head cells (from the read starting heads) that are not belonging to the layer to which they are assigned. If a value exceeds the top of a model layer to which it is assigned, the boundary value is turned into 99 and is converted to an active node. This option is applicable whenever NAMFILE_OUT is specified, whenever RUNFILE_OUT is specified, this keyword doesn’t have any effect.

DWEL=
(optional)

Use this keyword to overrule any intermediate dates specified for the WEL package in the PRJ file. By default DWEL=1 and WELLS are updated for each stress period, specify DWEL to suppress this.

DISG=
(optional)

Use this keyword to overrule any intermediate dates specified for the ISG package in the PRJ file. By default DISG=1 and ISG Segment Rivers are updated for each stress period, specify DISG to suppress this.

DSFR=
(optional)

Use this keyword to overrule any intermediate dates specified for the SFR package in the PRJ file. By default DSFR=0 and SFR Segment Rivers are NOT updated for each stress period, specify DSFR=1 to enable this.

ICONCHK=
(optional)

Use this keyword to correct the drainage levels automatically during a simulation. Whenever ICONCHK=1 the drainage level will be higher or equal to existing level from the RIV and/or ISG package. This prevents undesired circulation of groundwater between drainage system underlying an infiltrating river system. By default ICONCHK=0 and no corrections are performed.

ICONSISTENCY=
(optional)

Use this keyword to correct layer thickness of \(\le 0.0\) automatically. There are three options:
  • ICONSISTENCY=0
    there will be no corrections applied, this is the default value. Any layer thickness of \(\le 0.0\) yield a crash of the solver most probably. Use this option whenever there is confidence in the correctness of the model layering;

  • ICONSISTENCY=1
    in the case that an underlying interface \(i+1\) (i.e. the bottom of the same layer or top of the underlying layer) is \(\ge \) the current interface \(i\), the intersecting interface \(i+1\) will be corrected such that the model layer is at least 0.0 meter. Bear in mind that layer thickness are often not problematic for the iMODFLOW solver (MF2005), however, MF6 can handle those efficiently.

  • ICONSISTENCY=2
    this method applies a consistency modification to avoid layer with a zero thickness. Therefore, each model layer with a thickness less than the specified MINTHICKNESS (see next keyword) is converted to a layer thickness of MINTHICKNESS (or less if the total system (sum of aquifers and aquitards) is less). The permeability (including an appropriate value for the vertical anisotropy) is copied form the “underlying” layers from which the gained layer thickness is obtained. The total transmissivity and vertical resistance is checked after modification to ensure a correct modification, a significant difference (>0.01%) will terminate the process. System that are less then 0.25 \(\times \) MINTHICKNESS are excluded from the simulation.

MINTHICKNESS=
(optional)

Use this keyword to specify a minimal thickness (meters) for model layers as used in case the keyword ICONSISTENCY=2. The default value is MINTHICKNESS=0.1 meter.

INTSHD=
INTKDW=
INTKHV=
INTVCW=
INTKVV=
INTTOP=
INTBOT=
INTSF1=
INTSF2=
INTANF=
INTKVA=
(all optional)

Use these keywords to specify whether parameters need to be interpolated in cases where in the input is coarser than the simulation grid. bij default these are all equal to 1 which means an polynomial interpolation will be carried out. E.g. specify INTKDW=0 to suppress interpolation.

IDOUBLE=
(optional)

Use this keyword to save all results from the simulation in double precision. Whenever IDOUBLE=0 (default) a single precision value is saves, whenever IDOUBLE=1 a double precision is saved. Be ware that all files will be affected by this and therefore the total space that will be occupied by the results will be doubled.

IFVDL=
(optional)

Use this keyword to use the Formulae of ’De Lange’ ([De Lange et al. (2014)]) for the correction of river conductances. This keyword can be used whenever the PRJ file contains TOP and BOT definitions as well as KHV. The SFT package might be used to include permeabilities and thickness used by the formula, otherwise, if this SFT package is absent, de values from the model will be used. By default IFVDL=0 and no corrections are performed.

IDEFLAYER=
(optional)

Use this keyword to define the method to assign river-elements to model layers. Use one of the following options:
  • 1. IDEFLAYER 0
    apply this to assign the river-elements into layers based upon the water level and bottom elevation;

  • 2. IDEFLAYER 1
    apply this to assign the river-elements to all layers up to the layer in which the bottom elevation exists.

MINKD=
(optional)

Use this keyword to assign a minimal horizontal conductance KD (m\(^2\)/d) to maximize the computed conductances, internally, e.g. MINKD=0.01, by default MINKD=0.0.

MINC=
(optional)

Use this keyword to assign a minimal vertical resistance C (d) to maximize the computed vertical resistances, internally, e.g. MINC=1.0, by default MINC=0.0.

UNCONFINED=
(optional)

Use this keyword to include unconfined conditions for model layers, e.g. UNCONFINED=1,1,1,0,0,0 by default UNCONFINED=0 and model layers are confined. So, if NLAY=10 and UNCONFINED=1,1,1 this means that the first three model layers are unconfined, the remaining layers are confined. The values for UNCONFINED are:
  • UNCONFINED 0
    The model layer is confined, the saturated thickness is defined by the top- and bottom elevation per model layer;

  • UNCONFINED 1
    The model layer is unconfined, the saturated thickness is defined by the compute hydraulic head and the bottom elevation per model layer;

  • UNCONFINED 2
    The model layer is confined by the saturated thickness is defined by the starting heads and the bottom elevation per model layer.

It is obligatory to include the modules STO and SPY whenever unconfined conditioned are simulated for a transient model. iMOD will add and configure the WETDRY option automatically.

SPECIFICSTORAGE=
(optional)

This keyword is added to denote that specific storage is entered in the PRJ file instead of storage coefficients, by default (absence of this keyword) storage coefficients are applied.

IPEST=
(optional)

Use this keyword to include the parameter optimisation package PST, e.g. IPEST=1, by default IPEST=0 and the model is simulated conventionally.

PTEST=
(optional)

Use this keyword to simulate a set of parameter perturbation sequentially. This yields al combinations of the selected set of parameters perturbed within 0.0625 and 100.0, doubled for each simulation. In this end per parameter 9 simulation are carried, so if two parameters are considered this yields a matrix of 9x9 simulation, with three parameters 9x9x9.

IPESTP=
(optional)

Use this keyword to include the parallel parameter optimisation package PST, e.g. IPESTP=1, by default IPESTP=0 and the model is simulated conventionally. Whenever IPESTP=1, the optimization is steered by iMOD instead of via the executable specified for MODFLOW. Major advantage is the option to apply the sensitivity simulation in parallel.

SVD_EIGV=
(optional)

Specify the maximum explained variance from the eigenvalue decomposition, e.g. SVD_EIGV=99.9 to include 99.9% of variance present in the sensitivities, by default SVD_EIGV=99%. The values need to be maximal 100%, avoid values smaller than 99%.

NLINESEARCH=
(optional)

Specify the maximum number of line searches, by default NLINESEARCH=10. .

CMDHIDE=
(optional)

Specify CMDHIDE=1 to hide the command windows in which the models are running, this is the default. Whenever CMDHIDE=0, the command windows are displayed for each simulation.

NCPU=
(optional)

Specify the number of processors to be activated in the simulation of the sensitivity simulations. Whenever NCPU=8, 8 simulations will be carried out in parallel, the default is NCPU=1.

NSWAIT=
(optional)

Specify the number of centiseconds (100 = 1 sec) that iMOD need to wait before starting another model on a CPU, the default is NSWAIT=0. This might interfere too much if many CPU are used as they need to read form similar files, experiment with NSWAIT to balance the efficiency between IO and CPU optimally.

IEXPORT=
(optional)

Specify IEXPORT=0 to suppress the export to MF2005 files as they have been exported priorly. By default IEXPORT=1 and the model is exported completely. Use of IEXPORT=0 is advised for advanced users only as iMOD is not checking whether the existing export is accurate and resembles the used PRJ file.

SAVESHD=
SAVEWEL=
SAVEDRN=
SAVERIV=
SAVEGHB=
SAVERCH=
SAVEEVT=
SAVEMNW=
SAVELAK=
SAVESFR=
SAVEUZF=
SAVEFHB=
(all optional)

Use these keywords to save the hydraulic head per layer or/and results for the WEL, DRN, RIV, GHB, RCH, EVT, LAK, MNW, SFR, FHB and UZF package, e.g. SAVESHD=3,4,10 to note that model layers 3, 4 and 10 will be saved only, by default all keyword are 0, meaning no layers will be saved. Specify SAVESHD=-1 to denote that ALL layers will be saved, this is similar for the other packages, except for the SFR and UZF package, specifying more layers does not have any effect.

SAVEFLX=
(optional)

Use this keyword to include layers to be saved for the spatial fluxes in x,y and z direction, e.g. SAVEFLX=3,4,10 to note that model layers 3, 4 and 10 will be saved only, by default SAVEFLX=0, meaning no layers will be saved. Specify SAVEFLX=-1 to denote that ALL layers will be saved. Part of this, the BDGFFF, BDGFRF, BDGFLF and BDGBND will be saved.


Enter the following items whenever IGENMF6=0

NETWORKIDF=
(optional)

Specify an IDF file that represents the network for the simulation, e.g. NETWORKIDF=D:\MODEL \NETWORK.IDF. This keyword is optional, whenever this keyword is absent the network is defined by the first IDF file in the entered PRJ file or specified by the keyword WINDOW.

WINDOW=
(optional and NETWORKIDF is not specified)

Specify a window (X1,Y1,X2,Y2) for which the constructed RUNFILE will be clipped, e.g. WINDOW=125100.0,345000.0,135000.0,355000.0.

CELLSIZE=

Specify a cell size to be used, e.g. CELLSIZE=25.0. This keyword is necessary and read whenever the WINDOW keyword is entered.

BUFFER=
(optional)

Specify a buffer to be added to the specified window (WINDOW), e.g. BUFFER=1500.0. This keyword is optional and the default value is BUFFER=0.0.

BUFFERCS=
(optional)

Specify a maximal cell size in the buffer, e.g. BUFFERCS=100.0. This keyword is optional and read whenever BUFFER is specified and greater than 0.0 meter.

Example 1

FUNCTION=RUNFILE
RUNFILE_IN=D:\RUNFILES\MODEL.RUN
PRJFILE_OUT=D:\PRJFILES\MODEL.PRJ

The above mentioned example creates a projectfile D:\PRJFILES\MODEL.PRJ file out of the runfile D:\RUNFILES\MODEL.RUN.

Example 2

FUNCTION=RUNFILE
PRJFILE_IN=D:\PRJFILES\MODEL.PRJ
RUNFILE_OUT=D:\RUNFILES\MODEL.RUN
WINDOW=147000.0 448000.0 155000.0 452000.0
CELLSIZE=25.0
BUFFER=1500.0
SDATE=19940101120000
EDATE=20121231235959
ITT=3
IDT=2

The above mentioned example creates runfile D:\RUNFILES\MODEL.RUN, based on the content of the projectfile D:\PRJFILES\MODEL.PRJ for a specified window. The model starts at the \(1^{\rm st}\) of January 1994 at 12:00:00 am and ends at the \(31^{\rm st}\) of December 2012 at 23:59:59 am at uses two-weekly time steps.

Example 3

FUNCTION=RUNFILE
PRJFILE_IN=D:\PRJFILES\MODEL.PRJ
NAMFILE_OUT=D:\NAMFILES\MODEL.NAM
TIMFILE_OUT=D:\TIMFILES\MODEL.TIM
ISOLVE=1
MODFLOW=D:\PROGRAM\IMODFLOW.EXE

The above mentioned example creates a Modflow2005 configuration NAMFILE D:\NAMFILES\MODEL.NAM, based on the content of the projectfile D:\PRJFILES\MODEL.PRJ for a times discretisation specified in the *.TIM file D:\TIMFILES\MODEL.TIM. After that, it starts the simulation using the simulator D:\PROGRAM\IMODFLOW.EXE.


8.7.6IMODPATH-Function

The function IMODPATH computes flowlines based on the budget terms that result from the iMODFLOW computation. The IMODPATH function uses a very simple runfile. For more information see section 7.14.

FUNCTION=

IMODPATH

IRUN=
(optional)

Specify IRUN=1 to start a particle simulation, apply IRUN=0 to skip the particle simulation and perform a post processing solely, if IPOSTP=1. By default IRUN=1.

RUNFILE=
(optional)

Enter the name of the runfile (*.RUN) that describes the files, values and flags needed for the iMODPATH simulation, e.g. RUNFILE=D:\MODEL\SIM.RUN.
This keyword is compulsory whenever IRUN=1.
The content of such a runfile is as follows (leave out the keywords, see the example below):

NLAY

Enter the number of model layers, e.g. NLAY=8

NPER,ISTO

Enter the number of stress periods, .e.g. NPER=1 and whether fluxes from storage need to be read in, in case a transient simulation is carried out. The storage flux will correct the total water balance and influence whether an unbalance will denote a weak/strong sink. Whenever the absolute unbalance is larger than 0.01 m\(^3\)/d, iMODPATH will treat the location as a potential weak/strong sink. The parameter ISTO is optional and whenever it is absent the flow from storage is as assumed to be zero.

NISD
(optional)

Enter the number of ISD files to be computed, sequentially. Enter a value for this only whenever NISD\(\ge \)2. Leave this keyword out, whenever a single ISDFILE and OUTFILE is entered.

ISDFILE /
IPFFILE

Enter the name of the startpoint definition file ISD.
Repeat this file reference, together with file reference to OUTFILE for NISD-times whenever NISD is specified and NISD\(\ge \)2.
Check section 7.13 to see how to create this type of file. See section 9.20 for the actual syntax.
Alternatively to the ISD file an IPF file can be specified. It is compulsory to specify in this IPF file at least three columns whereby the first three columns are reserved for the x-, y- and z-coordinate.

OUTFILE

Enter the name of the result file. This file will contain the results calculated from of the previous given startpoint file (ISD/IPF). The extent will be added or replaced to the appropriate output format (IFF and/or IPF), e.g. D:\d:\RESULT. Repeat this, together with ISDFILE for NISD-times whenever NISD is specified and NISD\(\ge \)2.

IMODE

Enter the mode of the results to be achieved, use IMODE=1,0 for flowlines and IMODE=0,1 for endpoints only. For example IMODE=1,1 will save both particles in the IFF and IPF format.

IFWBW

Enter the direction of the tracing, use IFWBW=0 for a forward tracing and IFWBW=1 for a backward tracing.

ISNK

Specification on how to handle “weak”-sinks. Particles will continue at weak sinks for ISNK=1 as they stop at weak sinks for ISNK=2. The latter can be specified as a fraction for ISNK=3, see keyword FRACTION.

FRACTION

Specify the fraction of the total outflow to be a measure to determine whether particles should stop or continue in a model with a “weak”-sink. FRACTION=1.0 to let particles stop at a strong sink only, as FRACTION=0.0 act as particles will always stop, no matter the size of the total outflow (ISNK=1).

STOPCRIT

Enter the stop criteria. Specify STOPCRIT=1 to stop the particle as its age becomes equal to MAXT; specify STOPCRIT=2 to repeat the transient period in the time window as specified by the keywords SWINDOW and EWINDOW until the particles meets the MAXT criterion or stops in a weak/strong sink. Or, alternatively set STOPCRIT=3 to continue with the last results at the end of the time window until the particle terminates. This keyword STOPCRIT is only applicable whenever NPER\(>\) 1.

MAXT

Enter the maximum tracing time (days).

STARTDATE

Enter the startdate for the particle tracing, e.g. 19960414 to express the 14\({}^{th}\) of April 1994. This keyword is used only whenever NPER \(>\) 1, but you need to specify an artificial STARTDATE for NPER=1.

SWINDOW

Enter the start date for the time window in which the particle tracing will operate, e.g. 19960414 to express the 1\({}^{st}\) of April 1994. Only used whenever NPER \(>\) 1, but you need to specify an artificial SWINDOW for NPER=1.

EWINDOW

Enter the end date for the time window in which the particle tracing will operate, e.g. 20040328 to express the 28\({}^{th}\) of March 2004. Only necessary whenever NPER \(>\) 1, but you need to specify an artificial EWINDOW for NPER=1.

pictures/Ch-imod-batch/xWINDOW-explained.png

Repeat the following NLAY-times

IBOUND

Enter the boundary condition (IDF). Particle tracing will pass through boundary values \(<>\) 0 only.

TOP

Enter the top elevation (IDF or constant value) of a modellayer (m+MSL).

BOT

Enter the bottom elevation (IDF or constant value) of a modellayer (m+MSL).

PORAQF

Enter the porosity (IDF or constant value) of the aquifer (-).

PORAQT

Enter the porosity (IDF or constant value) of the aquitard (-). Specify this keyword for model layers < NLAY.


Repeat the following NLAY times and NPER times

BDGFRF

Enter the IDF file that represents the water budget (m\({}^{3}\)/day) along the x axes (columns) at the eastern border of each cell; positive flow is westwards, negative is eastwards.

BDGFFF

Enter the IDF file that represents the water budget (m\({}^{3}\)/day) along the y axes (rows) at the southern border of each cell; positive flow is northwards, negative flow is southwards.

BDGFLF

Enter the IDF file that represents the water budget (m\({}^{3}\)/day) along the z axes (layers) at the lower border of each cell; positive flow is upwards, negative flow is downwards. Specify this keyword for model layers 1 up to NLAY-1.

BDGSTO
(optional)

Enter the IDF file that represents the water budget (m\({}^{3}\)/day) that goes into storage; positive flow is going out of the storage, negative flow is going into the storage. This parameter is only needed whenever ISTO=1.

WINDOW=
(optional)

Specify a window (X1,Y1,X2,Y2) for which the constructed model will be simulated, e.g. WINDOW=125100.0,345000.0,135000.0,355000.0. This might increase the efficiency as only a part of the model need to be allocated and read in.

ICONVERTGEN=
(optional)

Specify ICONVERTGEN=1 to convert the results of the pathline simulation as well into a GEN (see 9.11) and DAT file (see 9.12). Bij default ICONVERTGEN=0 and no conversion will occur.

IPOSTP=
(optional)

Use IPOSTP=1 to include a post processing direct after the pathline simulation. This post processing will separate the IFF and/or IPF files to a given selection criterion. By default IPOSTP=0.

The following keyword are applicable only whenever IPOSTP=1

IFFFLOW=
(optional)

Enter the name of the IFF file (generated by the pathline simulation) to be processed, e.g. IPFFLOW=D:\RESULT\PATHLINES.IFF. By default no IFF file will be processed.

IPFFLOW=
(optional)

Enter the name of the IPF file (generated by the pathline simulation) to be processes, e.g. IPFFLOW=D:\RESULT\PATHLINES.IPF. By default no IPF file will be processed.

IPFFNAME=
(optional)

Enter the IPF file to be used to separate the content of the IFFFLOW and or IPFFLOW file names to the labels (ILABELCOL) as specified in the IPFFNAME, e.g. D:\INPUT\WELLS.IPF

IDFFLOW=

Specify an IDF file that will be used to map the points from the IPF file given at IPFFNAME on a network in order to match them with the results in the IPF and/or IFF file given at IPFFLOW and IFFFLOW, respectively, most common is to use a random IDF from the result map of the simulation results, used for the particle simulation, e.g. IDFFLOW=D:\RESULT\HEAD_STEADY-STATE_L1.IDF.

IXCOL=

Enter the column number in the given IPF file IPFFNAME that represents the X-coordinate, e.g. IXCOL=1.

IYCOL=

Enter the column number in the given IPF file IPFFNAME that represents the Y-coordinate, e.g. IYCOL=2.

ILABELCOL=

Enter the column number in the given IPF file IPFFNAME that represents the label, e.g. ILABELCOL=3. For each unique label, a separate IPF and/or IFF will be constructed.

ILAYCOL=

Enter the column number in the given IPF file IPFFNAME that represents the model layer, e.g. ILAYCOL=4.

TOPFNAME=
(optional)

Enter the IDF file to be used to identify the top of an interface that need to be used to separate IPF and/or IFF file that are underneath the interface, e.g. D:\INPUT\TOP_L1.IDF, by default no top is given and in that case all is valid. Any NodataValue in the IDF file will be used to exclude any particle.

BOTFNAME=
(optional)

Enter the IDF file to be used to identify the bot of an interface that need to be used to separate IPF and/or IFF file that are above the interface, e.g. D:\INPUT\BOT_L7.IDF, by default no bottom is given and in that case all is valid. Any NodataValue in the IDF file will be used to exclude any particle.

IEXTRACT=
(optional)

Enter the extract option for the particles, choose from the following:
  • • IEXTRACT=1
    Choose this option to extract the entire particle that satisfies the top- and/or bottom criterion, if only a single segment of the particle meets the criterion the entire particle is exported;

  • • IEXTRACT=2
    Choose this option to extract the particle until it satisfies the top- and/or bottom criterion, if only a single segment meets the criterion, the particle up to that location is extracted, the particle is not examined after that anymore, so a multiply agreement to the selection criterion does not hold;

  • • IEXTRACT=3
    Choose this option to extract the entire particle onwards after it satisfies the top- and/or bottom criterion lastly at first agreement, so whenever a particle hits the selection criterion the extraction will start after the last segment that met this selection criterion;

  • • IEXTRACT=4
    Choose this option to extract the entire particle that ends within any of the locations that satisfies the top- and/or bottom criterion.

By default IEXTRACT=4. This option is also only valid for IPF files that are entered at IPFFLOW.

Example 1

FUNCTION=IMODPATH
RUNFILE=D:\IMOD\IMODPATH.RUN

... and the content of the mentioned file IMODPATH.RUN:

pictures/Ch-model-functions/iMODPATH-run.png

Figure 8.2: Example of the content of an iMODPATH Run file, referred to from the iMODPATH.ini file.

The above mentioned example will do a particle simulation.

Note: iMOD creates an IMODPATH.RUN file each time iMODPATH is ran via the GUI (see "Start Pathline Simulation" in section 7.14). This file can be (re)used and refered to in Batch mode. Find the IMODPATH.RUN file in the folder: {installfolder} \IMOD_USER \MODELS \

Example 2

FUNCTION=IMODPATH
IRUN=0
IPOSTP=1
IFFFLOW=D:\RESULT\PATHLINES.IFF
IPFFLOW=D:\RESULT\PATHLINES.IPF
IDFFLOW=D:\RESULT\HEAD_STEADY-STATE_L1.IDF
IPFFNAME=D:\INPUT\WELLS.IPF
IXCOL=1
IYCOL=2
ILAYCOL=3
ILABELCOL=4

The above mentioned example will NOT do a particle simulation (IRUN=0), but performs a post processing solely.