#1 2022-05-16 10:05:22

Hansbau52

Member

From: Germany

Registered: 2022-05-10

Posts: 7

3D/DKT coupling, Create a vector

Hi community,

I want to create a vector that contains only the normal stress SIXX in a simple model. But it should be composed of SIXX from a 3D area and a DKT area (shell top side) of the model. Can someone please help me how to describe this.

Regards,
Hansbau52

Johannes_ACKVA

Member

From: Ingenieurbüro für Mechanik, DE

Registered: 2009-11-04

Posts: 753

Website

Re: 3D/DKT coupling, Create a vector

hello,

I think your question is not very clear. In a '3D'-modeled part SIXX is not a "normal stress", but the component in the global X-direction. In a 'DKT'-modeled part SIXX, SIYY, SIXY are the only 3 components of inplane-stress (be it on top or bottom side), there is no stress in the normal direction of a plate element. May be you can explain better . .

Johannes_ACKVA

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Hansbau52

Member

From: Germany

Registered: 2022-05-10

Posts: 7

Re: 3D/DKT coupling, Create a vector

Hello Dr. Ackva,

sorry, of course I described that quite badly.  Regardless of the type of model (3D/shell), I have normal stresses in the cross-section of a clamped beam, which result quite generally from bending and tension/compression (normal in the sense of orthogonal to the section surface).  In my simple model, the x-direction is the longitudinal axis of the beam and only bending normal stresses occur.
In the meantime I have learned a little.
In the attachment you will find a result picture. On the left the solid geometry and on the right the shell. The shell stresses are shown on the top side and on the bottom side. I have shifted the geometries accordingly by half the thickness. But I am not yet satisfied with this, because I want a uniform scale without a jump at the transition. I thought I might have to create a new result vector for this, which contains e.g. only SIXX ???

Best regards,

Hansbau52

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Attachments:
Spannung_SIXX_gekoppeltes_Modell.jpg, Size: 42.25 KiB, Downloads: 34