casefoam 0.2.0

Installing CaseFOAM

In order to use the Python module you need the PyFoam package.

install the package after cloning the repository with:

  $ pip install .

or via pypi by executing:

$ pip install casefoam

User’s Guide

For a full documentation change into doc and build the documentation for example as html.

$ cd doc/
$ make html
$ firefox build/html/index.html

parameter studies

The first step is the generation of the cases. We want to generate three column heights where each case has three grids with a differnt cell size.

cat genCases.py:

import casefoam

baseCase = 'damBreak'
caseStructure = [['height_02', 'height_03', 'height_04'],
                ['grid1', 'grid2', 'grid3']
                ]

def update_grid(a,b,c,d,e):
    return {
        'system/blockMeshDict': {'#!stringManipulation': {'varA': '%s' %a,
                                                          'varB': '%s' %b,
                                                          'varC': '%s' %c,
                                                          'varD': '%s' %d,
                                                          'varE': '%s' %e
                                                          }
                                }
    }

def update_height(height):
    return {
        'system/setFieldsDict': {'#!stringManipulation':
                                {'var_height': '%s' %height}}
    }

caseData = {
    'height_02': update_height(0.2),
    'height_03': update_height(0.3),
    'height_04': update_height(0.4),
    'grid1': update_grid(23,8,19,42,4),
    'grid2': update_grid(23*2,8*2,19*2,42*2,4*2),
    'grid3': update_grid(23*3,8*3,19*3,42*3,4*3)
}

# generate cases
casefoam.mkCases(baseCase, caseStructure, caseData, hierarchy='tree',writeDir='Cases')

There a three different options how the cases can be manipulated:

• replacing a string inside the specified files

• executing a bash script

• by specifying a dictionary

for details please see the user manual.

The script is executed by:

python genCases.py

This will the generate the following structure:

The cases can be started by running the newly created Allrun script

./Allrun

postProcessing

Three functions are avaiable for the postProcessing:

• time_series

• positional_field

• posField_to_timeSeries

For the damBreak test case we want to plot the freesurface position at a given time. For that, we use the positional_field function and get a pandas dataframe which we plot with holoviews

import casefoam
import matplotlib.pyplot as plt
import pandas as pd
import holoviews as hv
hv.extension('bokeh')

caseStructure = [['height_02', 'height_03', 'height_04'],
                ['grid1', 'grid2', 'grid3']]
baseCase = 'Cases'
surfaceDir = 'freeSurface'
surface = casefoam.positional_field(surfaceDir,'U_freeSurface.raw',0.3,caseStructure,baseCase)
surface.columns = ['x','y','z','Ux','Uy','Uz','col_height','res']
surface_ds = hv.Dataset(surface, [ 'col_height','res'], ['x','y','z','Ux','Uy','Uz'])

holoviews is optimized for the use for the jupyter notebooks. The %%opts arguments are used to modify the layout of the plot. holoviews renders an interactive plot which can be exported as html:

%%opts Scatter [width=600,height=600,title='freeSurface at 0.3s',tools=['hover']]
%%opts (muted_alpha=0.0)
surface_ds.to(hv.Scatter,'x','y').overlay('res')