PrePoMax (CalculiX FEA) - Tutorial 43 - Snap-fit

[@wgmg7746]

Świetny wzór na analityczną weryfikację zatrzasku. Podziwiam, Pana dociekliwość w szukaniu przykładów weryfikacyjnych.

[@FEAnalyst]

Dziękuję, faktycznie lubię wyszukiwać takie niestandardowe przypadki w literaturze.

[@peterszalai79]

Thank you, Jakub! 🙂👍❤️

[@DmytroRozputniak]

Nice work!

[@Syncopado]

Very insightful! Can you share where can I download that reference document (ccx-2.21)?

[@FEAnalyst]

Sure, CalculiX User’s Manual can be downloaded from here: www.dhondt.de/ccx_2.21.pdf

[@Syncopado]

@@FEAnalyst thanks!

[@pagnajonny]

Hi, you mentioned a forum page where this analysis was discussed; where can I find it?

[@FEAnalyst]

Hi, you can find this discussion here: calculix.discourse.group/t/snap-fit-contact-snagging-problem/2277

[@ellipse7]

Is Prepromax natively compatible with Linux systems?

[@FEAnalyst]

@@ellipse7 No, it’s made only for Windows and you need a virtual machine or an emulator like Wine.

[@jakubsobka2621]

I've seen no any penetration... What is the reason of use linear type of contact?

[@jakubsobka2621]

kzbin.info/www/bejne/qXaYeX6ZdsyLpNksi=5kEJCSIoUx152We4

[@FEAnalyst]

This case was problematic for contact formulation in CalculiX and required non-default stiffness specification which is recommended in many cases anyway.

[@jakubsobka2621]

@@FEAnalyst linear soft contact hasn't been necessary in that case... hard contact with friction should give good results because of no penetration

[@jakubsobka2621]

I'd love to see few more tutorials... cylindrical shell in hydraulic press, 3-point bending beam, CNC cutting, bullet penetration of steel plate and sheet metal stamping... 😎

[@FEAnalyst]

@@jakubsobka2621 The problem here was with convergence, sometimes reducing contact stiffness helps.

[@saifujiwara3941]

I've seen most of your tutorial and most of them not for the newbie/beginner like me, as chemical engineer, it is bit hard to me, since i have few basic of the "mechanical engineers or structural engineers", however i am really interested to learn this FEA/FEM, would you please advise the step to learn it (i,.e., suggested book, blog), thanks in advanced

[@FEAnalyst]

I can recommend "Practical Finite Element Analysis for Mechanical Engineers" by D. Madier and "Building Better Products with Finite Element Analysis" by V. Adams as well as some blogs like Enterfea but what really matters the most is a lot of practice. Fortunately, open-source software gives everyone this opportunity. Start from simple examples like beams and slowly build up complexity. Hand calculations, as shown in my tutorials, allow you to make sure your results are correct.

[@saifujiwara3941]

@@FEAnalyst thank you for the valuable advise. Yes i do agree with you learn something simple, verify it with hand calculation

[@surachatgumngen5526]

Since you have already provided on the "Snap-fit". How about the "Snap through Buckling" tutorial?😉

[@FEAnalyst]

That has been on my list since the video about nonlinear buckling of a shell. But I always include analytical calculations and for such a case this can be a problem, even for linear buckling. I’ll give it a try though.

[@jakubsobka2621]

Swoją w takim prostym przykładzie stosowanie kontaktów chyba mija sie z celem... Klips spornik wykonuje pewna pracę o pewnym określonym ugięciu (przemieszczenie punktu w kierunku pionowym) co tak jak y powinno być wystarczające do wyliczenia naprężeń i ewentualnie późniejszych historii jak np zmeczenia...??

[@FEAnalyst]

Można to uprościć i policzyć bez kontaktu zadając tylko odpowiednie wymuszenie, ale chodziło tu o pokazanie pełnego podejścia z kontaktem, który sprawiał w tym przypadku sporo problemów, więc była okazja omówić jego niestandardowe ustawienia i różne przydatne sztuczki.