usare joint contact

[ansyolitico]

Hi.
would it make sense to use in a static analysis both joints and contact?

type in a trivial lever system operated by a piston joints would go on the hinges and on the stem, while the rest of the structure the classic bonded, frictional .... everything because having parts connected with screws and therefore precarious, and moving parts (the lever and the piston) is difficult to model only with one method or another.. .

to live the two methods?

 

[Stan9411]

if the parts are in motion the analysis is not static .. you can put the type of bond you want but if the system is not at least isstatic the analysis will never converge

 

[ansyolitico]

but if you put a binding of frictionaless on the hinge so that it can't rotate it doesn't become static?

 

[Stan9411]

your description does not allow me to imagine the mechanism .. you should post an image

 

[ansyolitico]

like that.


because I saw this kind of setting... and I didn't think it worked

 

[Stan9411]

ok .. sincerely I have never made this use of ansys since I almost always found myself to analyze a single component and not a mechanism .. it is very interesting however that from the module "structural static" , setting variable loads and shifts in time, the solutor seems to automatically accept the possibility that the system has great freedoms.
very nice and I'm glad I learned it.

I think this tutorial shows you everything you need. contacts except for the “bonded” are all designed to grant relative movements: the frictionless allows the slide without friction. for this their nature, I think they are more appropriate to a “dynamic” analysis.

 

[ansyolitico]

It's all right.
....but using joints you have to use a different road that use contact....type hinge I always shaped it with a frictionaless to give the degree of freedom of rotation but doing so that mechanism does not simuli...so it would make sense to use all two types of constraints
?

 

[Stan9411]

decidedly yes! I think joints give much more uniqueness in the description of the degree of bond blocked ... with the frictionless or any other command for contacts, is at the good use of the user the correct modeling of the bond. in a few words with a joint you're sure of what you're modeling. .

 

[ansyolitico]

I don't understand


However it seems not to work so doing... the two systems conflict

 

[Stan9411]

I read the original answer ... I try to give you an opinion because after you showed me the video I went to read the ansys documentation on the functions of joints. at a quick glance I did not find reasons for conflict with contacts.. I can't do any tests right now, so I can't help you with why the analysis is in conflict.
I was trying to participate constructively in a discussion that might interest me in future projection .. if the thing is not liked to you we will wait for someone to enlighten us on if joint and contact can be used together.

Good luck

 

[ansyolitico]

Thank you.