So, this is not about FEM but I am posting it here since it is closely related and can be complementary with it and since I believe that those users that have interest in FEM/CFD will also be most competent using it and have interest in it.

Modelica

https://en.wikipedia.org/wiki/Modelica

First, here are some videos to get a more higher level understanding of its possibilities and get some inspiration from an commercial tool implementation of it with an parametric 3d model

https://www.youtube.com/watch?v=9RgdZUvEjPw

https://www.youtube.com/watch?v=MCqQuIShmLM

And next to get a bit deeper in to using Modelica directly

https://www.youtube.com/watch?v=39F___xyI0k

https://www.youtube.com/watch?v=zjHxU2KImxc

https://www.youtube.com/watch?v=8msC1CihT18

https://www.youtube.com/watch?v=-mvEUuc-sWE

https://www.youtube.com/watch?v=X2FgEFyfnfQ

https://www.youtube.com/playlist?list=P ... QA6sJiLpkB

https://www.youtube.com/playlist?list=P ... yiz1misw3a

http://book.xogeny.com/

https://www.modelica.org/

https://www.modelica.org/education/educ ... erview.pdf

http://www.bromans.com/david/publ/thesi ... broman.pdf

https://github.com/modelica/ModelicaStandardLibrary

https://github.com/modelica-3rdparty

https://www.openmodelica.org/ <- get openmodelica if you just want to quickly start playing with it

https://www.openmodelica.org/doc/Modeli ... 202-BT.pdf

https://www.mic-journal.no/PDF/2020/MIC-2020-4-1.pdf

https://www.openmodelica.org/doc/OpenMo ... de/latest/

https://www.openmodelica.org/openmodelicaworld/tools

https://github.com/OpenModelica/OpenModelica

https://jmodelica.org/

https://www.reddit.com/r/Python/comment ... ython_and/

https://simulationresearch.lbl.gov/modelica/

https://www.colorado.edu/lab/sbs/tools

https://vimeo.com/464446924

https://vimeo.com/464445684

https://vimeo.com/464376624

https://vimeo.com/464373709

https://github.com/christiankral/HanserModelica

https://www.youtube.com/watch?v=esGAcZ_ViRU

I believe it would be very useful to explore the possibilities to connect it with FreeCAD. I know there were in the past already some suggestions to use it for animations, but I hope that we can see from the above examples that it can be used for much much more and that its core powers are in system dynamics, solving differential, algebraic and discrete equations, lumped and logical models, systems engineering,...

While most of the usage examples that can be found around the internet are more from mechanical systems, and I am sure that there are many FreeCAD users that have a lot of interest in that, personally I am interested more in how it could be used in building construction (eg. structural calculations, thermal and energy calculations, noise transmissions, MEP and electrical systems,...)