On Fri, Jan 3, 2025 at 5:11 AM Gong Yujie <yc17470@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


--
What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
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