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2D loading of a rectangle; artefacts?
Posted Dec 18, 2015, 10:32 a.m. EST Geometry, Structural Mechanics Version 5.1 2 Replies
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Hi,
I am trying to do a very simple simulation of a 2D rectangle loaded by two blocks glued to the bottom of the rectangle, moving apart from each other. The attached picture is worth 1000 words. The two bottom lateral segments are being pulled apart horizontally. The middle section and the side vertical borders are free.
Why do I get that downward bulging in the middle? I suspect an artefact due to the load concentration at the interface between the "glued" and free borders. Any ideas on how I could get rid of it?
I am doing a stationary study with structural mechanics only, plane stress. I checked the large deformation option, and am applying the load in small steps.
Thanks in advance!
Claudio
I am trying to do a very simple simulation of a 2D rectangle loaded by two blocks glued to the bottom of the rectangle, moving apart from each other. The attached picture is worth 1000 words. The two bottom lateral segments are being pulled apart horizontally. The middle section and the side vertical borders are free.
Why do I get that downward bulging in the middle? I suspect an artefact due to the load concentration at the interface between the "glued" and free borders. Any ideas on how I could get rid of it?
I am doing a stationary study with structural mechanics only, plane stress. I checked the large deformation option, and am applying the load in small steps.
Thanks in advance!
Claudio
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2 Replies Last Post Jan 4, 2016, 7:00 a.m. EST
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Posted:
9 years ago
Dear Claudio,
The loads applied at the glued bottom of the rectangle cause a moment about the out-of-plane axis that tries to bend the block and create the deformation that you see. Note also that the material is experiencing large strains that are not accurately captured with an elastic material model even with the large deformation option. You need a material model that can handle large strains such as hyperelastic or elastic-plastic.
Nagi Elabbasi
Veryst Engineering
The loads applied at the glued bottom of the rectangle cause a moment about the out-of-plane axis that tries to bend the block and create the deformation that you see. Note also that the material is experiencing large strains that are not accurately captured with an elastic material model even with the large deformation option. You need a material model that can handle large strains such as hyperelastic or elastic-plastic.
Nagi Elabbasi
Veryst Engineering
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Posted:
9 years ago
Dear Nagi,
Thank you very much for your answer. I am aware that an hyperelastic material will improve the simulation accuracy; I plan on introducing a Mooney-Rivlin material model later on.
However, this will not solve the downward bulging of the free part of the block. Any ideas on how to correct this behaviour?
Best wishes, and happy new year!
Claudio
Thank you very much for your answer. I am aware that an hyperelastic material will improve the simulation accuracy; I plan on introducing a Mooney-Rivlin material model later on.
However, this will not solve the downward bulging of the free part of the block. Any ideas on how to correct this behaviour?
Best wishes, and happy new year!
Claudio