The frequency analisys is a nice tool to check contacts. It shows that you have defined one of them twice and there is other missing. That solves the
Did you want to upload a picture? It seems that it failed.
Those are the stresses from a frequency analysis, their values are relative (non-physical). You should carefully check the scaled deformed shapes in different modes in the results of this analysis. That’s the purpose. Then you can correct tie/contact definitions accordingly. Keep in mind that they were incorrectly assigned in your model.
If the tie-contact section is wrong, how can I fix this mistake? How should it be?
Make sure that each pair of surfaces that should be connected has a single contact definition so there are no duplicates and no omitted surface pairs. Missing interactions are well visible in frequency simulations - the surfaces become separated.
You can replace those contacts with tie constraints just for the purpose of frequency analysis to see if they work properly. Then there should be no separation
Then this top left beam seems to be missing interaction with the middle panel, right ? Check the definition and add it as necessary.
So if connections are working properly now, you can use them in your static analysis and see what happens.
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Hi, I was trying to simulate a bimetallic strip in unsteady state through an uncoupled temperature displacement step, and gave the values of Temp. wrt time in amplitudes tab. I then set the BCs as fixed on the bottom vertices of the strip and a temperature condition in which the magnitude was asked ( I don’t know what to put in there, my initial temp was 20) and ran the sim, causing this error. I have no idea what this means since the steady state problem was running just fine. Any help would be greatly appreciated!
Those are just warnings, not errors. Can you share the file ?
Also, I ran the simulation while deactivating step 1, which was just the step for practicing your bimetallic strip tutorial
Don’t use the Direct incrementation, it shouldn’t be chosen without a good reason and Automatic incrementation is recommended in most cases. Also, reduce the mesh density when debugging so that it doesn’t take too much time to run tests. And finally, avoid supporting individual nodes if it’s not necessary (better support small surface or edge partitions to avoid stress singularities).
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hi, can I contact you on mail for further queries?
You can send me a private message.
sent you the message on your mail
Wasn’t it Matej’s mail ? I don’t think mine is available anywhere here. I meant private message functionality on the forum.
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oh sorry I didnt know about this, can you send me a message, i dont know how to acess the private message functionality
Actually, the error refers to the final temperature so the one define with *TEMPERATURE (temperature defined field in PrePoMax). It has to be specified for the whole model even if part of it has only ambient (same as initial) temperature: Discrepancy in Results between ccx 2.13 and ccx 2.17 Versions - #4 by Calc_em - CalculiX (official versions are on www.calculix.de, the official GitHub repository is at https://github.com/Dhondtguido/CalculiX).