The CfdOF workbench aims to help users set up and run CFD analyses using the OpenFOAM® solver (www.openfoam.org, www.openfoam.com).
Please refer to the Readme file as this is the primary source of information, particularly on installing the workbench and its dependencies.
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
Before asking for help or reporting a problem, please note the following first:
- Developers may 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.
- Please make sure you have read and followed the instructions in the Readme file, particularly for installation issues.
- Make sure that the CfdOF workbench is up to date by going to Tools | Addon manager | CfdOF | Install/update selected.
- Make sure that that all dependencies are up to date by going to Edit | Preferences | CfdOF | Run dependency checker.
- Please ensure that OpenFOAM is correctly installed before reporting an issue with CfdOF. In Windows, CfdOF provides an installation link to the OpenCFD MinGW package for convenience. However, any issues with this installation are outside the control of the CfdOF workbench. Alternatively, BlueCFD-Core is also presently supported by CfdOF, which can be used as a fallback in case of problems with the default installation.
- On Windows, there can be issues with conflicting MSMPI versions. This is usually indicated by the following error:
The best remedy is usually to uninstall and reinstall the OpenFOAM (or BlueCFD) package, making sure to run the installer with administrator privileges if possible. If asked, answer 'yes' to reinstalling MSMPI.
Code: Select all
ERROR: Failed to post close command error 1726 ERROR: unable to tear down the job tree. exiting...
- 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, simply 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 demo case) 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'.
- Preferably report confirmed bugs at the project Github 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://github.com/jaheyns/CfdOF
- If you are running into an error with your model (not an error installing the software - see below for that), the quickest way for everyone is if your problem can be reproduced by an experienced user or developer. So:
- 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, and prevent time being wasted on blind speculation. The easier an issue can be reproduced, the easier it is to fix, so, If you do nothing else, please do this!
- Please re-do all steps from scratch to double-check the reproducibility of the problem from the saved state that you provide: Write mesh; Run mesher; Write case; Run solver.
- If your problem could not be reproduced by another user, or if it relates to installation of the software or its dependencies, then we need a lot more information from you in order to be of any help:
- Go to Help | About FreeCAD and click "Copy to Clipboard" and paste this information into your message. It is often important to know what system and version of the software is being used.
- Provide the output of running the dependency checker by going to Edit | Preferences | CfdOF | Run dependency checker as this provides information on the versions of external programs being used (most importantly, OpenFOAM).
- Provide all possible output when the error occurs 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
The following is a list of known training material:
- Official demo cases are provided in the 'demos' directory of the CfdOF module. The starting geometry is provided as well as the FreeCAD macros which reproduce the steps to set up the examples. These are kept up to date by the developers and used to test the workbench. They provide the most current reference for the capabilities of the workbench.
- Walkthrough slides. Slides are provided to walk you through the set-up process for some of the demo examples above. Note that these are based on earlier versions of the workbench and are not kept up to date, so some adaptation is required.
- Analysis of a blended wing aircraft design and more detail about how this was modelled using CfdOF by Walker Weathers.
- A ten-part video series about CfdOF by Tech Bernd (@Raedchen_im_System).
- Videos demonstrating a CFD simulation of flow through a pipe and simulation of external flow over an airframe by Joko Engineeringhelp
- Detailed tutorial on analysing flow through a pipe by Hawk JC Lee
- Detailed video walkthrough of setting up an analysis and setting up an analysis of a cyclone separator: part 1 / part 2 by Solvercube
- A demo video of simulating flow through a heat exchanger created by Paweł Łojek
- 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
- We appeal to you to investigate issues yourself as fully as you possibly can, and submit fixes to the project gitlab page. It is not sustainable for one volunteer developer to deal with all problems, particularly issues of interoperability of the different software tools on a variety of operating systems. These can be extremely hard to diagnose without having the same system setup.
- Any user assistance on the forum, as well as creating walkthoughs, demos, videos and documentation are very helpful in increasing the accessibility of the workbench.
- In terms of coding, refinements to the user interface would be a valuable way to start contributing without requiring deep knowledge of the existing systems.