Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

question closed

Please login with a confirmed email address before reporting spam

question closed


5 Replies Last Post Dec 20, 2021, 3:52 a.m. EST
Henrik Sönnerlind COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 2 years ago Nov 22, 2021, 3:53 a.m. EST
Updated: 2 years ago Nov 22, 2021, 3:53 a.m. EST

In the weak contribution, one term is . This means that must adapt so that the thickness direction stress is zero (in the weak sense).

-------------------
Henrik Sönnerlind
COMSOL
In the weak contribution, one term is \sigma_z \cdot \mathrm{test}(\epsilon_z) . This means that \epsilon_z must adapt so that the thickness direction stress is zero (in the weak sense).

Please login with a confirmed email address before reporting spam

Posted: 2 years ago Nov 23, 2021, 5:21 a.m. EST

That's what I expected but I never saw this in equation view in any version higher than 5, why?

That's what I expected but I never saw this in equation view in any version higher than 5, why?

Please login with a confirmed email address before reporting spam

Posted: 2 years ago Dec 8, 2021, 3:13 a.m. EST

When plane stress is chosen, there seems to be no constraint on the z stress in its strong or weak form, why?

When plane stress is chosen, there seems to be no constraint on the z stress in its strong or weak form, why?

Henrik Sönnerlind COMSOL Employee

Please login with a confirmed email address before reporting spam

Posted: 2 years ago Dec 9, 2021, 8:35 a.m. EST

The weak equation reads:

(-solid.Sl11*test(solid.el11)-2*solid.Sl12*test(solid.el12)-2*solid.Sl13*test(solid.el13)-solid.Sl22*test(solid.el22)-2*solid.Sl23*test(solid.el23)-solid.Sl33*test(solid.el33))*solid.d

Now, if you look in Equation View, you will find that solid.el33 is equal to the auxiliary degree of freedom wZ, representing the strain in the transverse direction. This DOF will then be adjusted so that the transverse stress solid.Sl33 is forced to be zero (in a weak sense).

-------------------
Henrik Sönnerlind
COMSOL
The weak equation reads: (-solid.Sl11\*test(solid.el11)-2\*solid.Sl12\*test(solid.el12)-2\*solid.Sl13\*test(solid.el13)-solid.Sl22\*test(solid.el22)-2\*solid.Sl23\*test(solid.el23)-solid.Sl33\*test(solid.el33))\*solid.d Now, if you look in *Equation View*, you will find that solid.el33 is equal to the auxiliary degree of freedom wZ, representing the strain in the transverse direction. This DOF will then be adjusted so that the transverse stress solid.Sl33 is forced to be zero (in a weak sense).

Please login with a confirmed email address before reporting spam

Posted: 2 years ago Dec 20, 2021, 3:52 a.m. EST
Updated: 2 years ago Dec 20, 2021, 3:52 a.m. EST

Thank you very much Dr Sönnerlind.

Thank you very much Dr Sönnerlind.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.