reading some feature list is capable to export in deformed mesh. within STL file format the results is exporting as user expect. depending on steps or position, it could be export in deformed or non deformed (original geometry)
i try to exporting in INP format at deformed position as previous steps, but the behavior of programs not as the same workflow in STL. still it saved in non deformed (original geometry) and the boundary condition set up also.
ability to export the mesh in deformed position with original element type could be useful feature since imperfection is play a role to predict strength/capacity of structural member/part.
That is true. I am just working on adding support for wear analysis (by a request). For this to work the deformed mesh would have to be exported. For now, only the geometry in a stl file can be exported but I will add the capability to export the deformed mesh. A the moment the inp export exports the whole model so will it be enough to export only the deformed mesh and its node, element sets and surfaces?
When it comes to imperfections, it would be great to have the possibility to add them in the form of combined and scaled linear buckling mode shapes. Unfortunately, CalculiX doesn’t have a keyword for that but it seems that GraphiX can do it with some commands: Nonlinear buckling of shell with imperfections (FEA) - YouTube
Maybe such functionality could be added to PrePoMax based on the current work on deformed mesh export.
i found a simple steps to make all these work done by add one line of command in PrePoMax - Edit keyword.
the advantages are in original model which can be stay available, CalculiX only overwrites the coordinate of nodes with one of file were previously saved.
currently i’ve done with CGX to save node coordinates at deformed positions, hopefully it’s interest to implemented in next or future versions of PrePoMax.
Abaqus and many other FE packages use buckling shapes (scaled, single or combine) approach to model imperfections. however, latest many researcher found these approach is not a general ways and it may inappropriate for most cases.
above feature make easy and fast in definition for user. but, ability to chose any deformed shapes to be used in analysis (Buckling, Frequency, Spectrum, User) to modeling imperfection could be better options since it give the user a flexibility.
This seems to me that a feature to create a user-defined result field combining the existing result fields with some equations is the first thing to add. Then a feature to create a new step result combining the existing step results and then a feature to export a deformed mesh. Does this make sense to you?
It can be placed outside of the model, this doesn’t influence the export. What I meant is that you should use assign a reference point to a rigid body constraint. Then you will see its number within the keyword. For example:
Searching for 2354 or 2355 (explanation below) shows the definition of this point under the *Node keyword.
I just checked to make sure and I can confirm that it works even if you don’t use the rigid body constraint. It will just be slightly harder to find this reference point among the definitions of other nodes but you should find it at the end of the *Node card. In fact, there will be two points with the same coordinates since CalculiX uses rot node in addition to ref node. The former is just a dummy node necessary to handle rotations within the rigid body.
The inp file exporter works well but there are issues with the importer:
What do you want to do with these ref points - use them for coupling constraints ? Then you can define such constraints using the Keyword Editor, without the need to export the inp file.
Even if inp file export is necessary for some reason (e.g. because keyword edits require modification of existing keywords which is not possible in GUI at the moment), it’s better to do it after setting everything else and then just run the analysis outside of PrePoMax using CalculiX executable. Then you can open the results file (.frd) in PrePoMax for postprocessing.
