by Qingfeng Xia, 2015 http://www.iesensor.com/HTML5pptCV

the team from CSIR South Africa, 2016

• Oliver Oxtoby http://www.linkedin.com/in/oliver-oxtoby-05616835
• Alfred Bogears http://www.csir.co.za/dr-alfred-bogaers
• Johan Heyns http://www.linkedin.com/in/johan-heyns-54b75511

Note: CSIR team has forked this repo into https://github.com/jaheyns/Cfd, focusing on usability for new users.

Meanwhile, this repo still targets at preparing real-world case files from FreeCAD goemetry for advanced users, which also means user needs to tweak the case files in production environment.

Features from CSIR fork will be picked up regularly in the future. Before the release of FreeCAD 0.18, the author will focus on implementing infrastructure for CFDworkbench , PR to FemWorkbench of FreeCAD directly.

Use only with FreeCAD-daily version since Dec 2016. Currently, only OpenFOAM (official 3.0 +) solver is implemented, tested on Ubuntu 16.04

This module aims to accelerate CFD case build up. Limited by the long solving time and mesh quality sensitivity of CFD problem, this module will not as good as FEM module. For engineering application, please seek support from other commercial CFD software.

1. Python code to run a basic laminar flow simulation is added into CfdWorkbench
2. An independent python module, FoamCaseBuilder (LGPL), can work with and without FreeCAD to build up case for OpenFOAM
3. A general FemSolverControlTaskPanel is proposed for any FemSolver.

1. only laminar flow with dedicate solver and boundary setup can converge, and I suspect the the current meshing tool, netgen is not ideal for CFD, which needs very thin layer near wall. Please download my 2 test file to evaluate for this stage.
2. result can only be viewed in paraview. but possible to export result to VTK format then load back to FreeCAD. (it is implemented in Oct 2016)

• install on Linux: Ubuntu 16.04 as a baseline implementation

• install on Windows 10 with Bash on Windows support: Official OpenFOAM (Ubuntu deb) can be installed and run on windows via Bash on Windows, but it is tricky to run windows python script to call the command with python via subprocess module

• install on MAC (not tested): As a POSIX system, it is possible to run OpenFOAM and this moduel, assuming openfoam/etc/bashrc has been sourced for bash

=============================================

• OpenFOAM (3.0+) sudo apt-get install openfoam once repo is added/imported

see more OpenFOAM official installation guide, make sure openfoam/etc/bashrc is sourced into ~/.bashrc

• PyFoam (0.6.6+) sudo pip install PyFoam

• gnuplot.py/gnuplot-py

optional:

• paraFoam (paraview for Openfoam, usually installed with OpenFoam)
• salome for mesihng
• gnuplot

Debian/Ubuntu: see more details of Prerequisites installation in Readme.md in FoamCaseBuilder folder

RHEL/SL/Centos/Fedora: Installation tutorial/guide is welcomed from testers

After Oct 2016, Cfd boundary condition C++ code (FemConstraintFluidBoundary) has been merged into official master

Make sure netgen and Gmsh function is enabled and installed

from github using git clone https://github.com/qingfengxia/Cfd.git

symbolic link or copy the folder into <freecad installation folder>/Mod, e.g, on POSIX system:

sudo ln -s (path_to_CFD) (path_to_freecad)/Mod

ALTERNATIVELY, use FreeCAD-Addon-Installer macro from https://github.com/FreeCAD/FreeCAD-addons

========================================

There is a test script to test installation of this FoamCaseBuilder, copy the file FoamCaseBuilder/TestBuilder.py to somewhere writtable and run

python2 pathtoFoamCaseBuilder/TestBuilder.py

This script will download a mesh file and build up a case without FreeCAD.

Similar with FemWorkbench

• make a simple part in PartWorkbench or complex shape in Partdesign workbench

• select the part and click "makeCfdAnalysis" in CfdWorkbench

which creats a CfdAnalysis object, FemMesh object, and default materail

• config the solver setting in property editor data tab on the left combi panel, by single click sovler object

• double click mesh object to refine mesh

• hide the mesh and show hte part, so part surface can be select in creatation of boundary condition

• add boundary conditions by click the toolbar item, and link surface and bondary value

• double click solver object to bring up the SolverControl task panel

select working directory, write up case, further edit the case setting up then run the case (currently, copy the solver command in message box and run it in new console)

Johan has built a case, see attachment test procedure on freecad forum

A simple example of cube pipe with one inlet and one outlet. https://www.iesensor.com/download/TestCfdCubePipe.fcstd Example setup, calculation will diverge.

========================================

=======================================

You can fork this module to add new CFD solver or fix bugs for this OpenFOAM solver.

There is a ebook "Module developer's guide on FreeCAD source code", there are two chapters describing how Fem and Cfd modules are designed and implemented.

https://github.com/qingfengxia/FreeCAD_Mod_Dev_Guide.git where updated PDF could be found on this git repo

This is an outdated version for early preview: https://www.iesensor.com/download/FreeCAD_Mod_Dev_Guide__20161224.pdf

Cfd is still under testing and dev, it will not be ready to be included into official in the next 6 m.

Currently route I can imagine: CFD workbench new developers fork official FreeCAD and my Cfd githttps://github.com/qingfengxia/Cfd.git.

Cfd workbench depends on Fem for meshing and boundary(FemConstraint) and post-processing, most of them are coded in C++ so it is hard to split from Fem. If you need add feature on above, you branch FreeCAD official, not mime (but do let me know, pull request will only accepted if it is fully discussed on forum and reviewed by other dev like Bernd, me). see my ebook on how to pull request. Any other cfd python code, do pull request me (my Cfd.git) e.g. I developed vtk mesh and result import and export feature, git directly to official Fem workbench.

User can install freecad-daily, and git update/install Cfd.git so all got updated code without pain for installation.