If would help to mention which other threads you found, because then we can avoid providing the same suggestion. Alas, you didn't do that.
So far I have tried to change numerous parameters of the FEM / Solver settings. These include mesh groups, input file splitting, number of CPU's and the matrix solver. Besides Gmsh, I also tried meshing through Netgen and I tried to use the "experimental" CalculiX solver.
As I tried to describe above, the problem is about the creation of the input file. The meshing works and if the input file (with strongly simplified geometry) can be created successfully, the calculation also works.vocx wrote: ↑Mon Apr 06, 2020 10:48 pmBe aware that FreeCAD is just a pre-processor for an external finite element solver. CalculiX is the most common solver used. So, where is your problem? In the meshing, input file generation, or solving? It could be the connection between FreeCAD and the Gmsh mesher, or maybe the actual CalculiX solver.
As I tried to explain above, the calculation does work if I simulate the fish tank and the sub-rack separately. The question was why it does not work together.
There is a problem with the self_weight. Doubleclicking does not open dialog-window.
I abstracted the extruded aluminium profiles consciously to rectangular blocks in order to simplify the networking etc. From the extruded aluminium profiles I know the moment of inertia. Therefore, I have calculated the moment of inertia for the rectangular blocks and adapted the Young's modulus of the aluminium profiles accordingly, thus ensuring that the flexural strength (= moment of inertia * Young's modulus) is the same. Hopefully that is just right
I have tested the developer versoin. In fact it seems to work a little better (the error occurs much later).thschrader wrote: ↑Tue Apr 07, 2020 4:05 pmI recommend the newest FC0.19 development snapshot for FEM.
https://github.com/FreeCAD/FreeCAD/rele ... g/0.19_pre
Do you have an idea how I could solve the problem with the self-weight boundary condition?
You use 4 different materials with different densities. There should be 4 entries for
So far I thought that the self-weight boundary condition refers to the whole fusion. I have not yet been able to create them for individual materials. But in principle this approach could lead in the right direction, because this would at least be an explanation why the input file cannot be created for the whole model, but for partial models without problems. I'll look at this intensively again tomorrow.
Currently I plan to use the following aluminium profiles: