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How to input a no rotation constraint
Posted 8 mag 2024, 13:47 GMT-4 Results & Visualization, Structural Mechanics, Physics Interfaces Version 6.2 8 Replies
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Im working on the same system I need to put a no rotation constrant on the top face of the lower flexure.
I added the image of the location of the no rotation constrant and a pdf of the system. In addtion I attach the mph file of the system.
What i did was I use a rigid connector at the location and constrant it rotation however I suspect it does not work correctly because in the first 2 mode the flexure is not bended correctly and the system was not rigid.
If there an another way to put a no rotation constrant on the solid mechanics interface that will be perfect.
Any help will be very useful.
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If you just want a sliding, no-rotation constraint, you can use a Symmetry condition. There, you can also select if the boundary has a true roller condition, or is allowed to translate in the perpendicular direction.
-------------------Henrik Sönnerlind
COMSOL
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hello Henrik Sönnerlind,
Thank you very much for your response I Have a question.
For the system I don't want any sliding i just want it to be able to move in all direction (x y and z) but not able to rotated in the x y and z( the result im looking for is in this image) for the Symmetry condition does putting a free displacement work?
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Using Free displacement in Symmetry will give you almost what you want. But there is still one rotation that is allowed then. The best option to constrain all three rotations is probably to use a Rigid Connector with the flexible formulation.
-------------------Henrik Sönnerlind
COMSOL
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hello one more question
what is flexible formulation on rigid connector?
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Hi Nelson,
In the Settings window for a Rigid Connector, you can choose, under Connection Type, Rigid or Flexible. Choose Flexible for the flexible formulation, which is useful, for example, when applying loads because it will reduce local constraint effects.
Best regards,
Magnus
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Once i add the rigid connector on the boundary to constrain rotation in x y and z direction, do I need to add another boundary condition on the same place as the rigid connector to not allow to rotate or the rigid connector is equal to a no-rotation constraint.
Thank you very much.
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You only set Constrained rotation in the Prescribed Rotation section of the Rigid Connector settings, and select all three checkboxes.
-------------------Henrik Sönnerlind
COMSOL
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hello Henrik Sönnerlind
thanl you very much I check this out to see if this work.