Problem: Elastic plate solver with 3 pins

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pwray
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Problem: Elastic plate solver with 3 pins

Post by pwray »

I have been using the elastic plate solver with various boundary conditions. No problem until the latest experiment.

I am trying to support the plate with three internal 'pins' (circular internal holes with fixed or soft BC).

When I do this, the model runs without error, but the eigenmodes show that the third pin has been ignored (it simply moves with the surface).
The mesh seems to be defined correctly, because if I reverse the order of the pin indexes in the BC clause in the sif file, then a different pin is ignored.

The gmsh geo and msh files, and the Elmer sif file, are attached.
Attachments
pinned_plate.zip
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kevinarden
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Re: Problem: Elastic plate solver with 3 pins

Post by kevinarden »

Boundary Condition 1
Target Boundaries(2) = 7 5 6 6
Name = "Fixed"
Deflection 1 = 0.0
Deflection 2 = 0.0
Deflection 3 = 0.0
End

The (2) means only read the next two values 7 and 5
that means 6 and 6 is ignored

if you want six included
Target Boundaries(3) = 7 5 6
pwray
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Re: Problem: Elastic plate solver with 3 pins

Post by pwray »

OMG, so stupid! I knew that, but concentrating on other things. As you would guess I am new to this.
Thanks, and sorry to waste your time.
pwray
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Re: Problem: Elastic plate solver with 3 pins

Post by pwray »

While I have you, I understand that the elastic plate solver puts the displacement in the X value of the result in the vtu file.
Can you tell me what Y and Z represent?
raback
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Re: Problem: Elastic plate solver with 3 pins

Post by raback »

Plate solver has normal displacement and its derivatives in (x,y) as the three degrees of freedom.
kevinarden
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Re: Problem: Elastic plate solver with 3 pins

Post by kevinarden »

You should have x, y, and z displacements as well as magnitude in the vtu file. Paraview shows magnitude as the default when displacement is selected but you can change it.
pwray
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Re: Problem: Elastic plate solver with 3 pins

Post by pwray »

Thanks.
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