Search found 19 matches

by jake77
Fri Jan 18, 2019 12:41 pm
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

In the same folder as FreeCAD.exe you will find gmsh.exe. This starts gmsh GUI. Export the geometry from FreeCAD as brep (use brep not step!), import in gmsh and start to play. If exact your preferences are taken the gmsh GUI crashes too, screen attached. Gmsh 4 should be tested here. If this happe...
by jake77
Fri Jan 18, 2019 9:44 am
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

The inverstigated structure is the pressurized part of a pressure vessel that is to be checked for stability according to DIN EN 1993-1-6 for external pressure (full vacuum in the vessel). The vessel itself has two such compartments, that are placed above each other. From the outside it looks like ...
by jake77
Fri Jan 18, 2019 7:56 am
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

open your file and just remesh, no change ... I use gmsh 3.0.6 on Debian Buster. Remeshing takes some time ( only on of12 core runs on 100%, but thats another story ... ) one or two minutes. - open your doppelstock file (BTW: what does doppelstock means in the regard of this cylinder? I only know d...
by jake77
Fri Jan 18, 2019 7:36 am
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

Guys, I just managed to create a mesh (in 20 mins... :-D) that then did not work due to memory allocation error (20.8M nodes). I have an 8 years old laptop with 8 GB RAM but a mobile processor - currently I'm just buring time trying to solve this problem. I'm glad you have results though 8-) For me ...
by jake77
Fri Jan 18, 2019 7:04 am
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

runs here too apart from the pressure problem (which is a FreeCAD limitation ATM for curved shell geometry and CalculiX DLOAD) ... has quite funny mode shapes ... Could you elaborate what exactly is the limitiation? I changed the way the external pressure is applied. It is on the cylinder now, not ...
by jake77
Fri Jan 18, 2019 7:01 am
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

take your file and change in solver from static to frequency and run the analysis. The pic was 10th mode shape ... That much is clear now. Linear buckling and modal results should look similar. My problem is not so much choosing the analysis type, but getting a correct mesh. What settings did you u...
by jake77
Thu Jan 17, 2019 8:39 pm
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

runs here too apart from the pressure problem (which is a FreeCAD limitation ATM for curved shell geometry and CalculiX DLOAD) ... has quite funny mode shapes ... Screenshot_20190117_202128.png This is probably some higher mode (unless the way supports are defined interferes...) but yes, this is wh...
by jake77
Thu Jan 17, 2019 8:33 pm
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

bernd wrote: Thu Jan 17, 2019 7:05 pm

Code: Select all

v 2.10
Do you really use ccx 2.10 !!! This is years old. You should use 2.15 or at least 2.14

For all the rest i will give some input later on ...
that was the one I found before installing FreeCAD and finding out it has one bundled. I'll check on this.
by jake77
Thu Jan 17, 2019 5:32 pm
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

So I spent the day with trying to solve my problem. I attached the model too look on (without mesh as suggested) if anyone is interested. The model has a simplified geometry, as the half-pipe shaped stiffeners should be a helix. I could create that but the geometry was warped for some reason and mes...
by jake77
Thu Jan 17, 2019 1:03 pm
Forum: FEM
Topic: Stress Result in a cylinder Shell
Replies: 42
Views: 4928

Re: Stress Result in a cylinder Shell

bernd wrote: Thu Jan 17, 2019 10:42 am
jake77 wrote: Thu Jan 17, 2019 10:01 am OK I see you have it regularly updated. I'll fire it up then.
you can get it here for windows, just unpack and run it https://github.com/FreeCAD/FreeCAD/releases

btw. compiling on windows int not that difficault, since we gone provide precompiled library pack.
Thanks, I already switched.