Hi, these tutorials are amazing thanks. I duplicated the tutorial step-by-step but am having a problem with defining the pressure load. The "pressure" type is not available in my version (1.3.5.1) so I am using "Uniform pressure" instead. But it does not allow me to select the inner edge of the pipe, or any edge for that matter. I only seem to be able to select parts of surfaces. The only thing I did differently was when defining the Sections, I used the "shell section" option rather than the "solid section" you seem to use. The reason for doing this is because the latter option does not allow me to specify a thickness... Could this be a bug or do you have any suggestions, please? Tx
@FEAnalyst
Жыл бұрын
Now regular pressure load is called uniform pressure because hydrostatic and imported pressure loads were added. Make sure that you select the right model space (2D plane strain) in the beginning. Then you have to use solid section and there should be the thickness option (maybe the Data tab is folded for some reason if you can't see it anywhere). You should also be able to apply pressure to edges. Try with Edge angle setting if the default one doesn't help. If you still encounter any issues, please report them on the PrePoMax forum since it might be a bug.
@johankotze
Жыл бұрын
@@FEAnalyst Thank you very much! It worked as you described.
@seymurhasanov4321
2 жыл бұрын
Hi thanks for the tutorial! It is really helpful and very informative. One question, is it possible to create a custom material as a function of position? Thanks
@FEAnalyst
2 жыл бұрын
Good question. Unfortunately, CalculiX doesn’t have any keywords to define spatially-varying material properties. But there is a workaround that should work if you don’t have to account for any thermal effects in your analysis. Namely, you can define temperature-dependent material properties and apply a defined field (both options are already supported in PrePoMax) with spatially-varying temperature values. In a static analysis without thermal expansion these won’t be the actual temperatures but just some user-defined field variables.
@seymurhasanov4321
2 жыл бұрын
@@FEAnalyst Thanks for the answer. And, is it possible to plot a stress-strain graph by capturing elastic and plastic regions?
@FEAnalyst
2 жыл бұрын
@@seymurhasanov4321 You can request history output to save stress and strain values for selected elements as a function of load increment. The results will be printed to the dat file and also available in the Results tab of PrePoMax. Just copy this data to Excel and combine it to create a stress-strain plot. There is also a separate output variable named PEEQ that gives you just the plastic strains and can be useful in many cases.
@seymurhasanov4321
2 жыл бұрын
@@FEAnalyst Awsome! Thank you
@konradriedel4853
2 жыл бұрын
thanks for the tutorial here as well, one more thing coming to my mind is how could that be used to calculate a shrink fit shaft hub connection with two circular parts and interference fit?
@FEAnalyst
2 жыл бұрын
That’s a very good question. In fact, I wanted to do a shrink fit analysis for this tutorial. Unfortunately, it turned out that contact in CalculiX (unlike in Abaqus) can’t resolve initial penetrations as shrink fits properly. CalculiX’s native pre- and postprocessor (GraphiX) offers a special command that utilizes MPCs to adjust the nodes and resolve the press fit but it seems to be the only way to do it in CalculiX.
@konradriedel4853
2 жыл бұрын
You may consider what is mentioned in cgx manual but i didnt manage to make it work properly from prepomax side: send dep indep abq areampc presfit s0.06 Which should force nodes with interference to move along to the desired coordinates
@FEAnalyst
2 жыл бұрын
@@konradriedel4853 Where have you entered this command? Normally, it's written in the GraphiX's command line. If you did some tests and found out that it doesn't work properly in CalculiX/GraphiX, maybe you could join this discussion and help us dispel the doubts: calculix.discourse.group/t/modeling-interference-fit-shrink-fit/603
@FEAnalyst
Жыл бұрын
After some tests and discussion with CalculiX dev it turned out that it's possible to resolve interference fits correctly with the default contact settings (of course without the ADJUST parameter which is used for strain-free adjustment). I just uploaded a new tutorial showing this.
@Matteo-lw8cl
2 жыл бұрын
Good evening. How can be modeled an interference fit in Prepomax? For example, between shaft and bearings?
@FEAnalyst
2 жыл бұрын
Check my answer to the question asked before by Konrad Riedel. CalculiX normally doesn't support interference fits but its native pre- and postprocessor (GraphiX) offers a command that adds MPCs which should do what shrink fit does. I haven't tested it yet though since I rarely use GraphiX.
@Matteo-lw8cl
2 жыл бұрын
@@FEAnalyst thank you. So, I should export the geometry with mesh in "*.inp" format, and then, implement the presfit with cgx?
@FEAnalyst
2 жыл бұрын
@@Matteo-lw8cl Yes, you can give it a try. It would be great if you could let me know if it happens to work. Even better if you join this discussion then: calculix.discourse.group/t/modeling-interference-fit-shrink-fit/603
@FEAnalyst
Жыл бұрын
After some tests and discussion with CalculiX dev it turned out that it's possible to resolve interference fits correctly with the default contact settings (of course without the ADJUST parameter which is used for strain-free adjustment). I just uploaded a new tutorial showing this.
@Matteo-lw8cl
Жыл бұрын
@@FEAnalyst Thank you for the support!
@tominmathew344
2 жыл бұрын
Hi, Is it possible to import any mesh file in PrePoMax?
@FEAnalyst
2 жыл бұрын
Yes, you can import the mesh using one of the supported formats: .unv, .vol, .inp and .mesh. You could create such a mesh using Salome or Gmsh for example.
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