OpenFOAM

Contents

OpenFOAM#

OpenFOAM is a Finite Volume method for CFD simulations with a wide range of applications across several areas of engineering and science. OpenFOAM has an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to solid dynamics and electromagnetics.

There are two main open-source versions of OpenFOAM, one developed by OpenFOAM foundation and another by the ESI Group. Inductiva API supports both versions, and you can choose which one you want to use by setting the version parameter when initializing the simulator. The default version is the one developed by the OpenFOAM foundation.

A single simulation via Inductiva API comprises several steps done via OpenFOAM

  • e.g., partitioning the domain, meshing, solvers and post-processing. Hence, to configure a simulation for OpenFOAM the user will need a set of configuration files that are organized in three folders:

  • time: containing individual files of data for particular fields, like initial values and boundary conditions that the user must specify. For example, for an initial condition at $, the initial conditions will be stored in the directory 0.

  • constant: contains files that describe the objects in the simulation and the physical properties of the application we are concerned.

  • system: contains all of the files that describe the simulation, including the solvers, the numerical parameters, and the output files. It must contain at least 3 files: controlDict where run control parameters are set including start/end time, time step and parameters for data output; fvSchemes where discretization schemes used in the solution may be selected at run-time; and fvSolution where the equation solvers, tolerances and other algorithm controls are set for the run.

All of these folders should be inside an input directory. Finally, to run a simulation the user needs to configure a list of dictionaries specifying the commands they want to execute on the backend. Below, we run the motorbike tutorial from OpenFOAM and show how this is done in practice.

The commands passed to the simulator follow the structure of OpenFOAM, that is, using the prefix runApplication the command will execute sequentially and with runParallel the command will use the maximum number of cores the machine has available. Hence, you don’t need to set the specific number of processes, the simulator will do that for you automatically. In particular, the decomposeParDict will be configured automatically and, at the moment, only the scotch decomposition method is available.

Example#

import inductiva

# Set simulation input directory
input_dir = inductiva.utils.download_from_url(
    "https://storage.googleapis.com/inductiva-api-demo-files/"
    "openfoam-input-example.zip", unzip=True)

# Set the simulation commands
commands = [
    "runApplication surfaceFeatures",
    "runApplication blockMesh",
    "runApplication decomposePar -copyZero",
    "runParallel snappyHexMesh -overwrite",
    "runParallel potentialFoam",
    "runParallel simpleFoam",
    "runApplication reconstructParMesh -constant",
    "runApplication reconstructPar -latestTime"
]

# Initialize the Simulator
openfoam = inductiva.simulators.OpenFOAM(version="foundation")

# Run simulation with config files in the input directory
task = openfoam.run(input_dir=input_dir, commands=commands, n_vcpus=4)

task.wait()
task.download_outputs()