8.6. Domain definition helpers

8.6.1. Introduction

One of ParFlow’s strengths is its customizability; you can practically define any type of hydrologic problem with it. One of the downsides of that, however, is that setting all the keys can be cumbersome, especially when starting a run from scratch. With the new DomainBuilder, Python-PFTools helps condense the setting of keys for many common problem definitions.

8.6.2. Usage of DomainBuilder

First, we’ll show some usage examples of loading tables of parameters within a ParFlow Python script:

from parflow import Run
from parflow.tools.builders import DomainBuilder

LW_Test = Run("LW_Test", __file__)

# ----------------------------------------------------------------------------

bounds = [
    0.0, 41000.0,
    0.0, 41000.0,
    0.0, 100.0
]

domain_patches = 'x_lower x_upper y_lower y_upper z_lower z_upper'
zero_flux_patches = 'x_lower x_upper y_lower y_upper z_lower'

DomainBuilder(LW_Test) \
    .no_wells() \
    .no_contaminants() \
    .water('domain') \
    .variably_saturated() \
    .box_domain('box_input', 'domain', bounds, domain_patches) \
    .homogeneous_subsurface('domain', specific_storage=1.0e-5, isotropic=True) \
    .zero_flux(zero_flux_patches, 'constant', 'alltime') \
    .slopes_mannings('domain', slope_x='LW.slopex.pfb', slope_y='LW.slopey.pfb', mannings=5.52e-6) \
    .ic_pressure('domain', patch='z_upper', pressure='press.init.pfb')

In this example, the 10 lines associated with the instantiation of the DomainBuilder class generate about 70 keys! As is possible with any other key setting, you can always overwrite the keys as necessary; the DomainBuilder is designed to help you get started. Once you instantiate the DomainBuilder object on a Run object, each method will set various keys with the given arguments.