Precise Simulation wrote

CFD2D wrote

I was thinking more of an Ergun equation. But if you can create equations yourself, that's great!

Yes, you can define your own PDEs or modify the pre-defined physics modes, see for example

https://www.featool.com/doc/physics.html#phys_ce

Precise Simulation wrote

CFD2D wrote

Such problems have already been dealt with in OpenFoam and if you can use all OpenFoam solvers, you can also tinker one yourself together. Or do I get the basic concept wrong?

Currently you can not use _all_ OpenFOAM solvers as it would involve far too much work to write custom interfaces for them all. There are built-in interfaces for laminar and turbulent single phase flow, as well as compressible Euler equations which correspond to the simpleFoam, pimpleFoam, and rhoCentralFoam solvers. If you need to use another solver you could possibly use FEATool to set up/export mesh and case files, run your custom solver externally, and re-import the solutions for postprocessing/visualization.

Precise Simulation wrote

CFD2D wrote

Ok, so I think its possible to create a whole process flowsheet with multiple parts of models
I saw that you can optimize the geometry in FEATool. I would like to optimize the distance between the tubes in the tube bundle reactor so that the flow of the cooling medium is low, but the conversion of the reaction localizes its optimum. In Star CCM + you can do this via the Design Manager. Can such cases also be dealt with in FEATool?

There is not built-in functionality for optimization, but you can certainly use the FEATool functions with the MATLAB Optimization toolbox as has been done by Prof. Yamazaki (note that there is no in-house expertise to help with optimization of this type)

https://www.featool.com/model-showcase/03_structural_mechanics_07_topology_optimization1

or parameter minimization and root finding with the fminbnd and fzero functions

https://www.featool.com/tutorial/2019/02/11/parameter-minimization-and-potential-flow-over-wing-profile.html
https://www.featool.com/tutorial/2019/01/14/inverse-fea-modeling-and-parameter-search-using-matlab-functions.html

or just setting up simple parametric runs

https://www.featool.com/tutorial/2017/11/13/cad-import-and-parametric-stress-displacement-simulation
https://www.featool.com/tutorial/2015/09/09/parametric-studies-with-featool-m-script-model-files

Note, that there is currently no GUI functionality for setting up and running parametric or optimization studies (like I assume StarCCM+ Design Manager is) so everything would have do be done I m-script file.