FreeCAD
The CfdOF workbench aims to help users set up and run CFD analyses using the OpenFOAM® solver (www.openfoam.org, www.openfoam.com).
Please see the Readme file for information on installing the workbench and its dependencies.
Disclaimer:
This offering is not approved or endorsed by OpenCFD Limited, producer and distributor of the OpenFOAM software via www.openfoam.com, and owner of the OPENFOAM® and OpenCFD® trade marks
Reporting problems
When asking for help or reporting a problem, please note the following:
- Developers only have time to respond to clearly demonstrated bugs. Of course, you are free to ask for help from community members, but it is unlikely that an issue with the workbench will be looked into unless you have taken time to demonstrate that there is a fault with the software rather than with the installation or problem setup.
- If at all possible please attach a saved .FCstd file and instructions for reproducing your problem from the saved state. This will greatly increase the chances of the issue being looked at by someone.
- Provide all possible output for debugging purposes:
- In FreeCAD, go to Edit | Preferences | Output window
and tick all five tick boxes on that panel (Record log messages, Record warnings, Record error messages, Redirect internal Python errors, Redirect internal Python output), and click OK. - Then, click View | Panels and tick Report View as well as Python Console.
- Now re-create the error and copy any output and error messages which appear on either the report view or the python console, not just the last line or error. A screenshot is OK if all the relevant output is shown.
- In FreeCAD, go to Edit | Preferences | Output window
- Go to Help | About FreeCAD and click "Copy to Clipboard" and paste this information into your message.
- Please make sure you have read and followed the instructions in the Readme file, particularly for installation issues.
- Please ensure that OpenFOAM is correctly installed before reporting an issue with CfdOF. In Windows, CfdOF provides an installation link to the ESI-OpenCFD MinGW package for convenience. However, any issues with this installation are outside the control of the CfdOF workbench. In case of problems, the ESI-OpenCFD Docker package and BlueCFD-Core are presently still supported by CfdOF and can be used as a fallback in case of problems with the default installation. Note that blueCFD does not work with the Conda package of FreeCAD at present.
- Make sure that both the CfdOF and Plot workbenches are up to date by going to Tools | Addon manager | CfdOF | Install/update selected (and repeat for 'Plot' instead of 'CfdOF').
- Make sure that that all dependencies are up to date by going to Edit | Preferences | CfdOF | Run dependency checker
- There is an infinite variety of ways in which a CFD simulation can go wrong. If a simulation crashes with no specific error message, it is likely because of numerical divergence; this usually means that some aspect of the setup is not right for the solver. Unfortunately, providing the final error code or error message is generally of no use in determining the cause in these cases. Some training in CFD may be required to debug the problem, but the best remedy is usually to start with the simplest possible form of the problem (or a known working tutorial problem) and build up complexity slowly. Again, you are welcome to ask for help from the community but developers will not have the time to provide general training in CFD.
- Please note that residuals are not guaranteed to converge: there simply is not a steady state solution to all problems. When there is a sufficiently abrupt angle in the geometry, vortices are periodically shed and only an unsteady solution exists. Then the residuals of the steady-state equations get 'stuck'.
- On Windows, there can be issues with conflicting MSMPI versions. The best remedy is usually to uninstall and reinstall the OpenFOAM (or BlueCFD) package. If asked, answer 'yes' to reinstalling MSMPI.
- Please re-do all steps from scratch to check the reproducibility of the problem: Write mesh; Run mesher; Write case; Run solver. If changes are made to the model between generating the mesh and running the solver, the cases can get out of sync.
- Preferably report confirmed bugs at the project gitlab page. The present forum is intended for community assistance and may not always be monitored by developers. Of course, we'll be grateful if you are able to fix the bug yourself and issue a pull request at https://gitlab.com/opensimproject/cfdof
The following is a list of known training material:
- A demo of simulating flow through a heat exchanger created by Paweł Łojek
- Example test problems. The starting geometry is provided as well as the FreeCAD macros which reproduce the steps to set up the examples. Slides are provided to walk you through the set-up process. Note that these are based on earlier versions of the workbench, so some adaptation is required.
- Blog article on setting up 2D flow over a cylinder by Rick Palo.
- Tutorial on setting up laminar flow in a tube created by Keshavamurthy Indireshkumar.
- A beginner's walk-through video created by @makkemal