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Re: less than impressed with Creo Sim 2.0

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A quick look

 

From the .rpt file

 

One immediate issue you have to look at ...

 

At the top of the .rpt file :

 

** Warning: Two faces (DBIDs: 83341938 & 83208508) on opposite

            surfaces in a contact (DBID: 82855602) are

            connected at a node (DBID: 82789300). This prevents

            the surfaces from moving completely apart during

            a contact analysis. If this is not what you

            intended, please edit your model appropriately.

 

 

Probably means that the boundary of one of your contact regions is is attached to the opposite surface when it possibly should be free to slide/separate,  This will mean load will be transferred through these nodes and the structure not move as it should. Local fastener forces will be affected.

 

One cause of this, for example, is the creation of a surface/volume region after the definition of a contact. The original contact now has to become 2 contacts and you only defined 1.

 

Review the run diagnostics, these will appear as orange dots. Select one and see what is highlighted in the model. You then have to reverse engineer the reason to fix it.

 

Ignore the following for now.

 

*** Warning: Large deformation and/or strain detected during contact analysis.

    More accurate results may be obtained if 'Calculate Large Deformations' is selected.

 

Switching on LDA will cause a ramp up in analysis time you don't need at the moment. Besides, it could  be inappropriate is material strains are low and the large movement is due to sliding.

 

 

The fastener forces. One shouldn't expect more than a few percent variation from preload values

 

Buffer# - 1.7e4 - ish ok?

Cylinder 312 to 2.3e4 - quite a range,,, suspicious

secondary - 712 to 1.6e3 ....mmmmmmmm

clamp3, insert1&2, promary4,5,6, secondary 3,5,6 small numbers, likely to be wrong (if these are fasteners).

tele# - all 7.5e3 -ish ok?

 

2. Causes of smaller than expected fastener tensions:

-Local contact region boundaries sticking to opposite surface (above)?

-Fastener surface regions (created by the software) running off the edge of a component/into tangent lines (rounds) overlapping neighbouring fastener regions.

 

Analysis time is reasonable.

 

 

From the .pas file, the residual norm 'collapses' in a well behaved manner, the contact solution seems good.


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