[petsc-users] Inquiry about PetscDS for discretization of second order system

[Matthew Knepley]

On Fri, Jan 3, 2025 at 5:11 AM Gong Yujie <yc17470 at connect.um.edu.mo> wrote:

> Dear PETSc developer group,
>
> I'd like to inquire that if PetscDSSetResidual can be used for second
> order system? Are there a DS function that is related to solve a system
> that contains second order time derivative such as time dependent linear
> elasticity problem.
>
> I found there is tutorial for elastostatics problem using PetscDS but this
> doesn't involve time discretization. In TS, there is alpha method for
> solving second order system, but I haven't found a tutorial using DS yet.
> Is there a way to combine PetscDS with the alpha method in TS?
>

I did not include the second derivative in the interface. Instead what I do
is rewrite it as a first order system using
v = \dot u. I hope to augment the interface sometime to add the second
derivative, but it really only applies to that
alpha integrator.

  Thanks,

     Matt


> Best Regards,
> Yujie
>


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experiments is infinitely more interesting than any results to which their
experiments lead.
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