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combining overlapping objects at selected boundaries

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Hello, I'm trying to combine objects which overlap with more boundaries. How can I select boundaries at which objects should be fixed? or how to split objects but only at selected boundaries?

In attachment there is an example picture. I want to combine object 3 with objects 1 and 2, but still leave objects 1 and 2 disconected at the boundary between them. Forming assembly I get 3 separated objects. Forming union I get 1 object, but without the 'cut' between 1 and 2? Does anyone know how to solve this problem?

Best regards, Szymon


4 Replies Last Post 1 nov. 2013, 06:48 UTC−4
Josh Thomas Certified Consultant

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Posted: 1 decade ago 31 oct. 2013, 15:00 UTC−4
Szymon-

I think you may need to split your system into three objects and use a form assembly. Then, under the definitions and physics set-up define identity/continuity of dependent variables on the boundaries that you would to be "connected." In this way, the boundary between object 1 and object 2 can be disconnected while the boundaries between object 3 and the other two objects can be connected.

--
Best regards,
Josh Thomas
AltaSim Technologies
Szymon- I think you may need to split your system into three objects and use a form assembly. Then, under the definitions and physics set-up define identity/continuity of dependent variables on the boundaries that you would to be "connected." In this way, the boundary between object 1 and object 2 can be disconnected while the boundaries between object 3 and the other two objects can be connected. -- Best regards, Josh Thomas AltaSim Technologies

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Posted: 1 decade ago 31 oct. 2013, 15:44 UTC−4
Thank You for reply.
I cannot find where to define 'identity/continuity of dependent variables'. Is it under identity pairs? I'm not sure if it will work for my aplication. I am using Solid mechanics to simulate deformations coused by internal stress. If I leave it as assembly of 3 objects and use identity pairs it still deforms as all objects are disconected.
Thank You for reply. I cannot find where to define 'identity/continuity of dependent variables'. Is it under identity pairs? I'm not sure if it will work for my aplication. I am using Solid mechanics to simulate deformations coused by internal stress. If I leave it as assembly of 3 objects and use identity pairs it still deforms as all objects are disconected.

Josh Thomas Certified Consultant

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Posted: 1 decade ago 31 oct. 2013, 16:19 UTC−4
Two places...

They need to be defined under Model>Definitions as either contact pair or identity pair boundaries.

Then under the Solid Mechanics physics under Pairs you define contact or continuity.

--
Best regards,
Josh Thomas
AltaSim Technologies
Two places... They need to be defined under Model>Definitions as either contact pair or identity pair boundaries. Then under the Solid Mechanics physics under Pairs you define contact or continuity. -- Best regards, Josh Thomas AltaSim Technologies

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Posted: 1 decade ago 1 nov. 2013, 06:48 UTC−4
thanks, It's working
thanks, It's working

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