[petsc-users] Problem with SNES convergence

[Rahul Samala]

Hello PetSc users,
1)  I have problem with SNES convergence. I call SNESSolve  in a time loop and use the inbuilt Jacobian feature. The code works fine for about 5380 time steps after which it breaks down. The solution till that point looks fine. I have used newtonls of type l2. (newtontr and others aren't working). Since I have used inbuilt Jacobian feature and the code worked for about 5000 time steps I don't understand the reason for failure, is it an incorrect function evaluation?  Attached are the outputs with -pc_type lu and ilu along with -snes_linesearch_type l2 -snes_converged_reason -snes_monitor -snes_view -ksp_converged_reason -ksp_monitor_true_residual
2)  How to get hold of failure signal, like Nonlinear solve DIVERGED_MAX_IT or DIVERGED_LINEAR_SOLVE so that whenever it occurs I can use a reduced time step and see if the code converges.
Thank you,Rahul.

output_ilu.txt

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output_ilu.txt


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output_lu.txt

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output_lu.txt


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