For acute installation issues, please post on the corresponding OpenFOAM Installation forum at CFD-Online.
This page explains how to install the foam-extend project 
on Mac OS X (the other main OSes have their own pages: Linux and Windows). If you have installed foam-extend on a platform that is not mentioned here or had to take other/additional steps for successful installation, please contribute and edit this page or post at OpenFOAM Installation forum at CFD-Online (and send a message to the maintainer).
To quote[1] from the release notes of the project:
- The foam-extend project is a fork of the OpenFOAM® open source library for Computational Fluid Dynamics (CFD). It is an open project welcoming and integrating contributions from all users and developers. Previously known as OpenFOAM-dev and OpenFOAM-extend, it contains bug fixes and performance improvements, as well as extensions and additional features provided by community contributors (see file ListOfContributors), such as dynamic mesh and topological change support, turbomachinery extensions including general grid interpolation (GGI), cyclic GGI and mixing plane, block-coupled matrix support, implicitly coupled conjugate heat transfer and other physics coupling, finite area method, comprehensive dynamic mesh (motion and topological changes) capability and GPU support. For a full list, see below and previous release notes at: [1]
- Version 4.0, nicknamed "Guimaraes", is the current version of foam-extend. The release continues the tradition and spirit of the original FOAM code developed by prof. Jasak and Mr. Weller during their time at Imperial College and released as the general purpose CFD/CCM package by Nabla Ltd. in 2000. In this spirit, we reverted 18 December 2013 to the original numbering scheme (foam-2.3.2, 13 December 2004) as release number 3.0. Visit foam-extend.org for more information.
- OPENFOAM is a registered trademark of ESI Group. OpenFOAM-extend and foam-extend are a community effort not endorsed by ESI Group.
In the following chapters and sections is explained how to generally install foam-extend-4.0 and related dependencies, such as ParaView, although you should first refer to the folder doc/buildInstructions/ on the official repository for dedicated instructions for each supported Operating System.
Contents
1 Installation Instructions
The following sections describe two ways on how to install foam-extend 4.0 on Linux Distributions. For instructions on how to install on Linux and Windows, see the respective wiki pages:
1.1 Installing from binary package
TODO: For now, try downloading the provided packages and following the instructions given in the folder foam-extend-4.0/macOS in the download area for foam-extend at SourceForge.net.
1.2 Installing from source code
TODO: For now, try following the instructions given at Installation/Mac_OS/OpenFOAM-1.6-ext, along with the instructions given at Installing from source code at the page for Linux.
2 First steps
After installing the foam-extend core, the first step should be to create the directory, where simulation cases will be held (this assumes that you have sourced etc/bashrc as described above):
mkdir -p $FOAM_RUN
When you have sourced etc/bashrc, you can use a shortcut to change to your run directory by typing:
run
You can now explore the tutorial cases, type:
tut
to change to the corresponding directory. To run a case, copy it to $FOAM_RUN and execute the solver application there.
The User Guide can be found inside the folder "doc/Guides-a4/". To know where this is located, run:
echo $WM_PROJECT_DIR/doc/Guides-a4
It can also be downloaded from here: UserGuide.pdf from foam-extend-4.0
For questions, please refer to the following forums:
- For general questions: OpenFOAM forum at cfd-online.com
- For specific installation questions: OpenFOAM Installation subforum at cfd-online.com
