flopy.modflow.mflpf module

mflpf module. Contains the ModflowLpf class. Note that the user can access the ModflowLpf class as flopy.modflow.ModflowLpf.

Additional information for this MODFLOW package can be found at the Online MODFLOW Guide.

class ModflowLpf(model, laytyp=0, layavg=0, chani=1.0, layvka=0, laywet=0, ipakcb=None, hdry=-1e+30, iwdflg=0, wetfct=0.1, iwetit=1, ihdwet=0, hk=1.0, hani=1.0, vka=1.0, ss=1e-05, sy=0.15, vkcb=0.0, wetdry=-0.01, storagecoefficient=False, constantcv=False, thickstrt=False, nocvcorrection=False, novfc=False, extension='lpf', unitnumber=None, filenames=None)[source]

Bases: flopy.pakbase.Package

MODFLOW Layer Property Flow Package Class.

Parameters:
  • model (model object) – The model object (of type flopy.modflow.mf.Modflow) to which this package will be added.
  • ipakcb (int) – A flag that is used to determine if cell-by-cell budget data should be saved. If ipakcb is non-zero cell-by-cell budget data will be saved. (default is 0)
  • hdry (float) – Is the head that is assigned to cells that are converted to dry during a simulation. Although this value plays no role in the model calculations, it is useful as an indicator when looking at the resulting heads that are output from the model. HDRY is thus similar to HNOFLO in the Basic Package, which is the value assigned to cells that are no-flow cells at the start of a model simulation. (default is -1.e30).
  • laytyp (int or array of ints (nlay)) – Layer type, contains a flag for each layer that specifies the layer type. 0 confined >0 convertible <0 convertible unless the THICKSTRT option is in effect. (default is 0).
  • layavg (int or array of ints (nlay)) – Layer average 0 is harmonic mean 1 is logarithmic mean 2 is arithmetic mean of saturated thickness and logarithmic mean of of hydraulic conductivity (default is 0).
  • chani (float or array of floats (nlay)) – contains a value for each layer that is a flag or the horizontal anisotropy. If CHANI is less than or equal to 0, then variable HANI defines horizontal anisotropy. If CHANI is greater than 0, then CHANI is the horizontal anisotropy for the entire layer, and HANI is not read. If any HANI parameters are used, CHANI for all layers must be less than or equal to 0. Use as many records as needed to enter a value of CHANI for each layer. The horizontal anisotropy is the ratio of the hydraulic conductivity along columns (the Y direction) to the hydraulic conductivity along rows (the X direction). (default is 1).
  • layvka (int or array of ints (nlay)) – a flag for each layer that indicates whether variable VKA is vertical hydraulic conductivity or the ratio of horizontal to vertical hydraulic conductivity. 0: VKA is vertical hydraulic conductivity not 0: VKA is the ratio of horizontal to vertical hydraulic conductivity (default is 0).
  • laywet (int or array of ints (nlay)) – contains a flag for each layer that indicates if wetting is active. 0 wetting is inactive not 0 wetting is active (default is 0).
  • wetfct (float) – is a factor that is included in the calculation of the head that is initially established at a cell when it is converted from dry to wet. (default is 0.1).
  • iwetit (int) – is the iteration interval for attempting to wet cells. Wetting is attempted every IWETIT iteration. If using the PCG solver (Hill, 1990), this applies to outer iterations, not inner iterations. If IWETIT less than or equal to 0, it is changed to 1. (default is 1).
  • ihdwet (int) – is a flag that determines which equation is used to define the initial head at cells that become wet. (default is 0)
  • hk (float or array of floats (nlay, nrow, ncol)) – is the hydraulic conductivity along rows. HK is multiplied by horizontal anisotropy (see CHANI and HANI) to obtain hydraulic conductivity along columns. (default is 1.0).
  • hani (float or array of floats (nlay, nrow, ncol)) – is the ratio of hydraulic conductivity along columns to hydraulic conductivity along rows, where HK of item 10 specifies the hydraulic conductivity along rows. Thus, the hydraulic conductivity along columns is the product of the values in HK and HANI. (default is 1.0).
  • vka (float or array of floats (nlay, nrow, ncol)) – is either vertical hydraulic conductivity or the ratio of horizontal to vertical hydraulic conductivity depending on the value of LAYVKA. (default is 1.0).
  • ss (float or array of floats (nlay, nrow, ncol)) – is specific storage unless the STORAGECOEFFICIENT option is used. When STORAGECOEFFICIENT is used, Ss is confined storage coefficient. (default is 1.e-5).
  • sy (float or array of floats (nlay, nrow, ncol)) – is specific yield. (default is 0.15).
  • vkcb (float or array of floats (nlay, nrow, ncol)) – is the vertical hydraulic conductivity of a Quasi-three-dimensional confining bed below a layer. (default is 0.0). Note that if an array is passed for vkcb it must be of size (nlay, nrow, ncol) even though the information for the bottom layer is not needed.
  • wetdry (float or array of floats (nlay, nrow, ncol)) – is a combination of the wetting threshold and a flag to indicate which neighboring cells can cause a cell to become wet. (default is -0.01).
  • storagecoefficient (boolean) – indicates that variable Ss and SS parameters are read as storage coefficient rather than specific storage. (default is False).
  • constantcv (boolean) – indicates that vertical conductance for an unconfined cell is computed from the cell thickness rather than the saturated thickness. The CONSTANTCV option automatically invokes the NOCVCORRECTION option. (default is False).
  • thickstrt (boolean) – indicates that layers having a negative LAYTYP are confined, and their cell thickness for conductance calculations will be computed as STRT-BOT rather than TOP-BOT. (default is False).
  • nocvcorrection (boolean) – indicates that vertical conductance is not corrected when the vertical flow correction is applied. (default is False).
  • novfc (boolean) – turns off the vertical flow correction under dewatered conditions. This option turns off the vertical flow calculation described on p. 5-8 of USGS Techniques and Methods Report 6-A16 and the vertical conductance correction described on p. 5-18 of that report. (default is False).
  • extension (string) – Filename extension (default is ‘lpf’)
  • unitnumber (int) – File unit number (default is None).
  • filenames (str or list of str) – Filenames to use for the package and the output files. If filenames=None the package name will be created using the model name and package extension and the cbc output name will be created using the model name and .cbc extension (for example, modflowtest.cbc), if ipakcbc is a number greater than zero. If a single string is passed the package will be set to the string and cbc output name will be created using the model name and .cbc extension, if ipakcbc is a number greater than zero. To define the names for all package files (input and output) the length of the list of strings should be 2. Default is None.

Notes

Examples

>>> import flopy
>>> m = flopy.modflow.Modflow()
>>> lpf = flopy.modflow.ModflowLpf(m)
classmethod load(f, model, ext_unit_dict=None, check=True)[source]

Load an existing package.

Parameters:
  • f (filename or file handle) – File to load.
  • model (model object) – The model object (of type flopy.modflow.mf.Modflow) to which this package will be added.
  • ext_unit_dict (dictionary, optional) – If the arrays in the file are specified using EXTERNAL, or older style array control records, then f should be a file handle. In this case ext_unit_dict is required, which can be constructed using the function flopy.utils.mfreadnam.parsenamefile.
  • check (boolean) – Check package data for common errors. (default True)
Returns:

lpf – ModflowLpf object.
Return type:

ModflowLpf object

Examples

>>> import flopy
>>> m = flopy.modflow.Modflow()
>>> lpf = flopy.modflow.ModflowLpf.load('test.lpf', m)
write_file(check=True, f=None)[source]

Write the package file.

Parameters:check (boolean) – Check package data for common errors. (default True)
Returns:
Return type:None