flopyrw

An extension of FloPy to write input simulation files for MODPATH-RW with Python.

Overview

Provides classes extended from the modpath module in flopy adapted to specific structures required by MODPATH-RW. Also introduces new package writers required by the program, consistent with the Documentation of Input-Output.

Quickstart

Install

To install the package from source, clone the repository:

git clone https://github.com/upc-ghs/flopyrw

and install

pip install -e /the/path/to/flopyrw/

You can also install the current release from PyPI:

pip install flopyrw

Use it

Classes follow the same logic than flopy, configuring packages on top of a MODFLOW flow-model object. For example, the flopy quickstart case:

import os
import flopy
from flopyrw import modpathrw

ws   = './mymodel'
name = 'mymodel'
sim  = flopy.mf6.MFSimulation(sim_name=name, sim_ws=ws, exe_name='mf6')
tdis = flopy.mf6.ModflowTdis(sim)
ims  = flopy.mf6.ModflowIms(sim)
gwf  = flopy.mf6.ModflowGwf(sim, modelname=name, save_flows=True)
dis  = flopy.mf6.ModflowGwfdis(gwf, nrow=10, ncol=10)
ic   = flopy.mf6.ModflowGwfic(gwf)
npf  = flopy.mf6.ModflowGwfnpf(gwf, save_specific_discharge=True)
# Same than in flopy quickstart,
# but with an aux var for concentration.
chd  = flopy.mf6.ModflowGwfchd(
        gwf,
        auxiliary=['CONCENTRATION'],
        stress_period_data=[
            [(0, 0, 0), 1.,1.],
            [(0, 9, 9), 0.,0.]
        ]
    )
budget_file = name + '.bud'
head_file   = name + '.hds'
oc = flopy.mf6.ModflowGwfoc(gwf,
        budget_filerecord=budget_file,
        head_filerecord=head_file,
        saverecord=[('HEAD', 'ALL'), ('BUDGET', 'ALL')]
    )
sim.write_simulation()
sim.run_simulation()

# Create a modpathrw model
# By default executable is 'mpathrw'
mprw = modpathrw.ModpathRW(flowmodel=gwf)

# Random walk options
modpathrw.ModpathRWOpts(
        mprw,
        timestep = 'min',
        ctdisp   = 0.1,
        courant  = 0.1,
        dimensionsmask=[1,1,0], # Random walk in x,y and not in z
    )

# Dispersion parameters 
modpathrw.ModpathRWDsp( mprw, alphal=0.1, alphat=0.01,  dmeff=0.0 )

# Basic package
modpathrw.ModpathRWBas( mprw, porosity=0.3 )

# Define the solute source
# In forward tracking, only cells with injecting flow-rate release particles
modpathrw.ModpathRWSrc(
        mprw,
        sources=(
            'CHD', # package name
            [            
                [
                    'CONCENTRATION', # aux variable
                    0.001,           # particlesmass
                    (4,4,1)          # template
                ], 
            ],
        ),
    )

# Configure the simulation 
simconfig = {
    'simulationtype'    : 'rwendpoint', 
    'trackingdirection' : 'forward',
    'weaksinkoption'    : 'stop_at',
    'weaksourceoption'  : 'pass_through',
    'stoptimeoption'    : 'specified',
    'stoptime'          : 20.0,
}
mprwsim = modpathrw.ModpathRWSim( mprw,  **simconfig )

# Write the input files
mprw.write_input()

# And run 
mprw.run_model()

# Get output and plot
head   = gwf.output.head().get_data()
bud    = gwf.output.budget()
epoint = flopy.utils.EndpointFile( os.path.join( ws, mprwsim.endpointfilename ) ) 
spdis  = bud.get_data(text='DATA-SPDIS')[0]
qx, qy, qz = flopy.utils.postprocessing.get_specific_discharge(spdis, gwf)
pmv = flopy.plot.PlotMapView(gwf)
pmv.plot_array(head)
pmv.plot_grid(colors='white')
pmv.contour_array(head, levels=[.2, .4, .6, .8], linewidths=3.)
pmv.plot_vector(qx, qy, normalize=True, color="white")
pmv.plot_endpoint( epoint.get_alldata(), zorder=10, s=4, linewidth=0.5, edgecolor='k' )

Note: In order to run a model via the interface a MODPATH-RW executable is required.

Testing

A suite of automated tests is available verifying different aspects of the interface and the program. In order to run these tests, some additional dependencies are required, which can be installed with:

pip install ".[test]"

You can follow the FloPy test guidelines for running and debugging tests.

Run the complete test suite from the folder autotest with the command:

pytest -s -v 

Resources

• flopy
• MODPATH-RW
• MODPATH
• modpath-v7
• modpath-omp