Elmer Discussion Forum

After checking the solver code I think a given Pre Strain is used only in special cases where the effect of geometric stiffness is activated (Stability Analysis = True or Geometric Stiffness = True). If you update to get the change https://github.com/ElmerCSC/elmerfem/commit/48ade7a16ddaeee4ceefe731...

Do you know whether this change in the routines will happen soon? If you update to obtain the change https://github.com/ElmerCSC/elmerfem/commit/7a166454a4559e7518da7f1ae79ab01f1aa44250 it might now be possible to apply Conforming BC in connection with a 1-D model. I also added a simple test https:...

Do I need to put additional input there? I would expect not as CBC should just replace the dofs with the corresponding node and checked a test . I think there is a problem in the library subroutines that prevents the creation of constraints when the boundary is defined in terms of point (101) eleme...

Here the keywords "Quadratic Approximation" and "Use Piola Transform" relate to the 3-D solvers where the discretization is done in terms of curl-conforming (edge element) basis functions. The 2-D version uses standard basis functions and doesn't need these commands. However it m...

Some comments on the BC named as "symmetry": - to obtain symmetry the normal component of the velocity should be set to be zero, together with the do-nothing (default) BC for the temperature - if a component of velocity is specified, the corresponding component of the surface traction cann...

Suitable BCs are explained in Section 13.2.2 of the documentation https://www.nic.funet.fi/pub/sci/physics/elmer/doc/ElmerModelsManual.pdf as "For example, outgoing waves may be approximated by setting Z = −rho_0 c and ZT = −iω/c on the outflow boundary". That is, one has to give also an im...

Thanks, your changes have now been merged. I noticed a small mistake in a size specification of memory allocation. It is also fixed in the devel branch.

-- Mika

Hi,

I think you have done right code modifications to allow for a normal-tangential BC with UMAT. They might well be worth creating a pull request.

-- Mika

I made a small change to the devel branch so that mass-proportional damping (Rayleigh Damping Alpha) for translational motions can now be given for the beam solver, whereas giving Rayleigh Damping Beta = ... causes a warning message.

The beam solver doesn't yet understand the Rayleigh damping parameters, but adding the Rayleigh damping would be an easy modification