Department of Engineering

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The ABAQUS FAQ


9. ABAQUS - CAE




Q9.1 : It is sometimes difficult to figure out whether something is possible using CAE or not how can I find out?

Look at the Keyword Reference manual and find the reference for the keyword. Then follow up the reference in the Analysis User's manual.
Then look for the ABAQUS CAE/usage label. This will explain whether it is possible to use the CAE to specify a particular keyword or not.


Q9.2 : In applying pressure the wrong surfaces were being picked and since ABAQUS does not have the option to highlight the entity before selection I have to start all over again from scratch. Is there a way around this problem?

Yes. Use the CTRL key to deselect the surfaces wrongly selected ie re-select the incorrectly selected surface(s) while holding down the CTRL key.


Q9.3 : It is difficult to choose interiors surfaces for example a hollow sphere where pressure is being applied in the internal surface.

Click on the icon to select surfaces in the interior. Then select all the surfaces in the exterior and interior and then hold down the CTRL key and click on the surfaces in the exterior.
If you accidentally clicked and de-selected a surface on the interior hold down the SHIFT and select the surface again.


Q9.4 :When I am making selection occasionally make a wrong selection especially if it is string of nodes again I have to start from scratch?

Use the CTRL key when re-selecting the nodes selected by mistake.
Alternately use the Selection Icon which allows highlighting entities before selection.



Q9.5 :It is easy to instance more than one instance of a part. Not easy to delete it I tried suppressing it.

Choose View --> Assembly Display Options and in the dialogue box choose the Instance tab. The various part instances will be listed. In the column marked Visible all the parts will be ticked.
If you had already specified loading and boundary conditions on the part instances you will have to make sure you delete the one with the least specification.
You can un-tick certain parts and click on APPLY to establish which of the duplicate instances to be deleted. Leave it visible and then choose Features --> Delete and click on the redundant part to delete it. Then return to the previous dialogue box and make all the parts visible.


Q9.6 :After analysing the results I found more than one instant which was not intended. How do you detect these beforehand?

See the answer to Q9.5.


Q9.7 : Having carried out a quarter model I wanted to analyse the full model. It was trying to copy translate each quarter and then rotating to make the full model1 with out mirroring option at the assembly level. Is there an alternative?

If you had sketched the quarter model then re-enter sketch mode and save the sketch. Then create a part again and load the sketch, mirror it and place it and delete the lines along the axis of symmetry which would become the lines in the interior and not required.


Q9.8 : I have carried out an analysis with quarter model making use of the symmetry however I would like to be able to display the results on a full model. Is that possible?


Yes. Choose View --> DB Display options....
In the dialogue box Choose the Mirror/Pattern tab and tick the appropriate mirror planes for this example, planes HZ and AX and then click on APPLY.
The full model should be is display.


Q9.9 : I have carried out a 2D model however I would like to be able to display it in 3D so that cress distribution along the boundary can be easily visualised. Is that possible?

Yes. Choose View --> DB Display options.... In the dialogue box Choose the Sweep/Extrude tab


Q9.10 : I would like to merge 2 separate parts which have a common edge but would like to retain the boundary so that I can ass sing different material properties to the two parts. Is this possible?

Yes it is possible.
in the Assembly module using Instances -> Merge/Cut ... option.
This will bring the Merge/Cut form. Here select the two part instances and then toggle the Retain Boundary option.
  • The other alternative which reaches the same end point but taking an alternate route is to create a single part (which is a combination of the two original parts). Then partition this part along the boundary. Since the end product is the same whichever option is the most convenient that should be followed.


    Q9.11 : Can one tie 2 un-matching regions together?

    The same method as outlined for the matching regions is a adopted. There only needs to a common region/zone in contact for it to be tied along the common zone.
    In the following figure the overlapping region is shown in the Magenta (for clarity this is shown shaded). In defining the tied zone the larger rectangles are specified respectively and ABAQUS will work out the overlapping zone.



    Q9.12 : How does one model the interface conditions between the 2 regions of a bimetallic strip which are bonded together?

    Use the partition option as a first choice. To specify the TIE, in the Interaction Module, Constraint ---> Create and choose TIE.



    Q9.13 : In making a full model I keep getting the message internal limes are not permitted.

    Yes interior lines are to be avoided as it confuses ABAQUS.


    Q9.14 : I remote login to a server from my PC using X-win 32 and I find that carrying out any work bordering on the impossible when I use zoom in/pan which do not appear to have any effect. It is also tedious/cumbersome to turn the model around to specify boundary conditions on the far side/face.

    In the menu View and choose option Specify View and try the options to pan, zoom etc.


    Q9.15 : When I partitioned a part that had boundary condition, loading and interaction specified on it all got un-set and I had to re-specify these again.

    Yes it happens. Plan ahead and always do the partition first and then do the load interaction specification and meshing.


    Q9.16 : I want to be able create a template of various sections and define section properties so that I am able to add the actual members later on. However this appears not to be possible.

    It is possible. Create the Material properties first and then create the sections and the profiles and then associate these with the corresponding material properties and then save the CAE file. Then this file can be used as a template.


    Q9.17 : A previously created and saved CAE file appears to be corrupted when tried to open it subsequently. Is it possible to re-create the CAE file?

    Yes it is possible to re-create the CAE database. First rename the corrupted CAE file. Then use the following from the command line :
    abaqus cae recover=<analysis-id>.jnl
    
    If the corrupted cae file was named abcd.cae then use the command :
    abaqus cae recover=abcd.jnl
    
    Therefore it is a good idea to keep the *.jnl file and also keep it up-to-date.
    © Cambridge University Engineering Dept
    Information provided by abaqus-support
    Last updated: 18 December 2011