mf
Mario,
But of course you have to tweak stuff once the basic building blocks are in place, engineering is complex, and so should be their CAE models.
I apologise if my comment was to generic, brutal? You are correct on all your comments.
I'm talking about basic structural building blocks in 'linear' statics or modal. If the 'blocks' do not work properly and/or needs hacking on a per model basis, like with the tied contacts, then it is not good enough for me.
I'll try again. In production design/FEA cycles at concept design stage on a complex assembly, parts change all the time, coz packaging space does. Designers have to re-design parts at the speed of light, and so have FEA teams to 'plug' them in into complex assemblies for fast look/see, report back to the design team.
If every time I had to plug a new part in my 50-part assembly, I had to partition faces and the like and play with the tolerance (distance) value, it'll never make it in time for prototyping --> production.
There is nothing to fiddle with tied contacts. The UI finds the pair of surfaces automatically in the whole assembly. You visually check they make sense, the solver takes care of all else. It is a super fast method well proven over decades in automotive, aerospace, etc.
I think code_aster fails on tied contacts on 2 key areas:
1.- It doesn't know at the start if the slave nodes i8ntersect the master surfaces. Big fail, since at this 1st pass the solver already rules out nodes not involved in the contact, regardless of the dist_max value, no fiddle should be required.
2.- Without the adjust parameter (automatic by the way), the nodes that do find intersection with the master in 1.-; can be 'moved' onto the master. In this way, you do not over-constrain the moments, as per my sketch in previous posts on the pairing.
Without those in place you have no general method to work fast with assemblies. The funny thing is that code_aster must already have an algorithm to do that in the 'real' non-linear contact definition. I believe they haven't fully linked all up with what they already have.
