PrePoMax & CalculiX - A Preview of Shell Fuctionallity
ฝัง
- เผยแพร่เมื่อ 12 ก.ย. 2024
- A new version of the free PrePoMax pre and post-processor for the CalculiX FEM solver will offer a full set of features for performing a shell based finite element analysis.
Download link and installation instructions for PrePoMax: lace.fs.uni-mb....
![[FULL EP.73] เปิดบ้าน 70 ล้าน "แป้ง Zbing" ยกมาทั้งญี่ปุ่น l เคหสถานบานปลาย l One Playground](http://i.ytimg.com/vi/YBnJhTt07Pg/mqdefault.jpg)
Awesome! That was the most anticipated new functionality for me. Can’t wait to use it.
Hope you enjoy it!
velikh pozdrav iz njemacke super tool hvala puno na svi koju su radili na taj Software hvala puno
Hvala.
Great, can't wait for the new feature.
However, as a beginner, i would like to know whether prepomax has manual book?
Unfortunately not. There are only TH-cam videos that show how to work with the software.
This software is very user-friendly so you should be able to learn it quickly with no need for manual. And if you know Abaqus then it’s even easier.
It would be nice to see examples of buckling and buckling of shells.
Yes, I agree. I will try to prepare more examples in the future.
@@MatejBorovinsek Thank you for your answer. The most important example is how to set up a nonlinear analysis and a plastic material.
Спасибо
Super! I noticed that some BCs and a connection (rigid link, you call it a "constraint") are referred to nodes. Wouldn't be worth to refer bc, loads and links to geometrical entities (edges, surfaces, ...)?
Well, if you remesh, all will be all right as long as you use geometry based selection which was used in the preview.
hi,
CalculiX is capable doing nonlinear analysis for both type (material & geometry), so it can do non-linear buckling analysis. successful of these analysis known much depends and sensitive on initial geometric imperfection definitions. most FEA software and regulation codes gave such a guidance based on scaled deformed geometries of eigen mode shapes .
since CalculiX does not have similar Abaqus *Imperfection keywords, so another approach is required. it could be useful if scaled of deformed node mesh geometries are allowable to save inside PrePoMax GUI's. and i hope it's on to-do list due to crucial steps.
best,
Yes, that could be implemented. But probably multiple eigen-shapes will have to be combined for the end result. Please send me an e-mail so we can discuss this in detail.
@@MatejBorovinsek thank you much for appreciates, i will contact further by mail.
I didn't find the 0.9 version, please upload that
Its a preview. The new version will be released soon.
When will the thermal module come?
The support for temperature-displacement simulations is planned but there is no time schedule jet.
I've downloaded the new version (0.9) but I can't import any geometry (solid or shell) because "The work directory does not exist" error pops up.
If it is a .dev version, go to the Settings and selecr the working directory and Calculix exe file path.
@@MatejBorovinsek Thanks, it seems to work now. But I’ve noticed another issue - all imported parts are visualized incorrectly. They consist of some unconnected surfaces (even when they are solid). I tried changing display settings but it didn’t help.
Please use the official release version, which is already online.
@@MatejBorovinsek Works great now, thanks. Is it possible to disable shell thickness visualization in postprocessing ?
Gumball yes and no. The 3D representation is the result of how Calculix works. It extends all shell elements into 3D elements. There is an option to output only shell visualisation at the middle of the extended solid element. The problem is, that only results at the middle of the solid element are displayed so no bending stresses can be observed.
hi, it's long waited features, ..
even shell element is not works as good as solid element for the CalculiX solver due to MPC's existence. still useful element, it would help me a lot in modeling tube/hollow intersection quickly.
displaying top & bottom face with light and dark colors are common in other FEA prepocessor, options in menus for each of these faces also required to define surface contact. another frequently use are layered shell element by composite options to capture better in plasticity stress/strain distribution along thickness.
mostly i use NETGEN mesher inside SALOME, looking of second mesh with quad dominant activated. seems the result around holes to an edges has a quad distortion. there's an option to reduced these problems using chordal error and limit size by curvatures options are checked/active. i will study meshing and check again later after the latest versions of PrePoMax released and downloadable,
thank you,
Thank you for all the comments. There is a built-in option to show and even invert the geometry face orientations but showing other face sides using a darker colour is a nice idea. At the moment only surfaces on the positive normal side can be selected so, in order to have a working contact, the surface orientation must be flipped if other surface side is needed.
I will check the possibility to improve the quad meshes but I did not notice such options in the nglib library.
And I know about the composite option but I never had the idea to use multiple layers to simulate the plastic response. Great idea and I will definitely check it out.
@@MatejBorovinsek thank you for interest to consider above general commons in FEA shell element usability.
yes, improved options in quad dominant mesher using Nglib has not found in stand alone version also. i didn't know exactly, only known get better in results. but it seems use external commands to take values from trimmed between min and max sizes of number of segments per edges/radius.
regarding to layered shell options, it can reduced poorly performance and avoid pitfalls if only one layer of shell elements are used. extracted from official documents,
** Shell element S4 expanded to solid C3D8I: cannot be used in *DYNAMIC calculations, has controlled hourglassing, (ed. still questionable for one layers only)
** Shell element S4R expanded to solid C3D8R: small elements are required to capture a stress concentration at the boundary of a structure,. massive hourglassing, displacements are completely wrong, but stress field is still correct.
** Shell element S8 expanded to solid C3D20, badly for isochoric material behavior, i.e. for high values of Poisson's coefficient or plastic behavior. too stiff in bending
**Shell element S8R expanded to solid C3D20R: high stress concentrations at the surfacr e of a structure might not be captured if the mesh is too coarse. problems in node-to-face contact calculations
** if the user manually define layer by duplicated mesh with offset options, it will generate knot for every nodes and deformations result may lead to be too stiff
even shell element in CalculiX had many limitations, it's a solid-shell 3d and still superior compared to classical shell element 2d. for example is Raasch hook and pre-twisted beam problems.
@@MatejBorovinsek hi, you may skip about composite menus since it can be access trough Edit Keyword features. however i did not success to run properly due to PrePoMax (current release) by default are ignoring pre-defined Materials i set. it has been shown and tagged as deactivated, can you reproduced my problems? thank you
@@syont Yes, that is right. The material is deactivated if it is not used. The reason is, that if the plastic material is written in the .inp file, the solver detects it and does a non-linear analysis even if the material is not used in any section definition. So I deactivate all unused materials. I could deactivate only non-linear materials (if they are not used) in the future it this helps?
@@MatejBorovinsek sorry, i forgot to check and mentions it is an imported model from INP files. actually the problems does not happen for scratch modeling in PrePoMax. also materials and shell section can be simple by re-defined and overwrites if necessary using Edit Keyword features. thank you
Hi friend. can be calculated: frequency, fatigue.
Frequency yes, fatigue no.
@@MatejBorovinsek ah ok thanks. where can I see in detail all the capabilities of the software?
@@rfuentelzar I added the link to the download page where all the information about the most important features is also published.
You can create a forum page.
I want to be support
The stand-alone home page is something for the future. And it will also include a forum where experienced users can help other users to solve their problems.
This software is wonderful but it's not getting enough attention from FEM users. I think this software not recognized enough.
Thank you. Any ideas of spreading the word are welcome.
@@MatejBorovinsek is legal to write a tutorial contains bunch of output materials from this software? provides mirror links or distributed CD soft-copy are allowable? please add license, term of use in about menus or help/documentation. due to these issues about copyright and restriction may cause all user to keep quiet. thank you
Yes, it is legal to use the software for tutorials.
@@MatejBorovinsek many thanks, i think i should writes a legal letters by email before.
is possible to hiding date & time stamps in output of analysis result windows? i did not found in 'Settings/Status block' menus. since low impressions may come from the student who reads someday, years in the future.
Unfortunately not at the moment.
Ver.0.9.0 !!