Failure due to stiffness?

[Liserion]

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Question

Hi,

so when running my simulation I keep getting the error:

The following occurred in the TimeStepper 'IterationAdaptiveDT' of type IterationAdaptiveDT.

Solve failed and timestep already at dtmin, cannot continue!

I also included my errors from the HPC and the kernels.. Without the Diffusion in the micro.i the simulation runs fine. So I am thinking that the simulation gets stiff. However, the simulation used to run fine with the exact parameters (that was 5 years ago tho).

So my question is: Is it correct that the simulation gets stiff and is this due to newer libraries? Have I made a mistake while updating the kernels?

The link to my git: https://github.com/Liserion/3dcurrentcollector

Any help is appreciated, thank you!

[GiudGiud]

Hello

Have you tried these instructions?
https://mooseframework.inl.gov/moose/application_usage/failed_solves.html

You can notably check if the problem did become stiff.
Also we would like to see the full console log

[Liserion]

another question: do I need to register MultiApps?
I just got the error
Task add_multi_app is not registered to build Problem derived objects
and when I

./babbler-opt --show-syntax | grep -n "MultiApp"

nothing comes up

[GiudGiud]

Hello

You can order the parent app and MultiApp solves by setting the execute_on parameters of order of calculation is a concern

You can also see postprocessor output to the console to check.

The error you are getting for registration is likely due to a mistake in the input file. Can you please paste the MultiApp block in your parent app here?

[Liserion]

###################################################
### For the two-level framework
###################################################
[MultiApps]
  [./micro]
    type = CentroidMultiApp
    app_type = babblerAPP
    use_displaced_mesh = false
    execute_on = 'TIMESTEP_END'
    # sub_cycling = true
    sub_cycling = true
    input_files =  micro.i
    block = cathode
  [../]
[]

 [Transfers]
  [./c2_to_micro]
    type = MultiAppVariableValueSamplePostprocessorTransfer
    multi_app = micro
    execute_on = SAME_AS_MULTIAPP
    direction = to_multiapp
    source_variable = ce
    postprocessor = c2_from_macro
  [../]
  [./phi1_to_micro]
    type = MultiAppVariableValueSamplePostprocessorTransfer
    multi_app = micro
    execute_on = SAME_AS_MULTIAPP
    direction = to_multiapp
    source_variable = phis
    postprocessor = phi1_from_macro
  [../]
  [./phi2_to_micro]
    type = MultiAppVariableValueSamplePostprocessorTransfer
    multi_app = micro
    execute_on = SAME_AS_MULTIAPP
    direction = to_multiapp
    source_variable = phie
    postprocessor = phi2_from_macro
  [../]
#  [./J_to_micro]
#      type = MultiAppVariableValueSamplePostprocessorTransfer
#      multi_app = micro
#      direction = to_multiapp
#      source_variable = J
#      postprocessor = J_from_macro
#      execute_on = SAME_AS_MULTIAPP
#    [../]
#   #####################################
#   ## Cs_surface to macro
  [./cs_from_micro]
    type = MultiAppPostprocessorInterpolationTransfer
    multi_app = micro
    execute_on = 'TIMESTEP_END'
    direction = from_multiapp
    variable = cs
    postprocessor = cs_surface
    displaced_source_mesh = false
    displaced_target_mesh = false
    num_points = 3
    power = 2
    radius = -1
  [../]
  ## Cs_surface to macro
  [./soc_from_micro]
    type = MultiAppPostprocessorInterpolationTransfer
    multi_app = micro
    execute_on = 'TIMESTEP_END'
    direction = from_multiapp
    variable = soc
    postprocessor = socp
    displaced_source_mesh = false
    displaced_target_mesh = false
    num_points = 3
    power = 2
    radius = -1
  [../]
#   ###########################
#   # [./sigmaH_from_micro]
#   #   type = MultiAppPostprocessorInterpolationTransfer
#   #   multi_app = micro
#   #   execute_on = 'TIMESTEP_END'
#   #   direction = from_multiapp
#   #   variable = SigmaH
#   #   postprocessor = SigmaH
#   #   displaced_source_mesh = false
#   #   displaced_target_mesh = false
#   #   num_points = 3
#   #   power = 2
#   #   radius = -1
#   # [../]
#   #########################
#  [./damage_from_micro]
#    type = MultiAppPostprocessorInterpolationTransfer
#    multi_app = micro
#    execute_on = 'TIMESTEP_END'
#    direction = from_multiapp
#    variable = Damage
#    postprocessor = Damage
#    displaced_source_mesh = false
#    displaced_target_mesh = false
#    num_points = 3
#    power = 2
#    radius = -1
#  [../]
[]

This is the original

###################################################
### For the two-level framework
###################################################
[MultiApps]
  [./micro]
    type = CentroidMultiApp
    app_type = babblerAPP
    use_displaced_mesh = false
    execute_on = 'INITIAL TIMESTEP_END'
    # sub_cycling = true
    sub_cycling = true
    input_files =  micro.i
    block = cathode
  [../]
[]

 [Transfers]
  [./c2_to_micro]
    type = MultiAppVariableValueSampleTransfer
    to_multi_app = micro
    execute_on = 'INITIAL TIMESTEP_END'
    source_variable = ce
    variable = c2
  [../]
  [./phi1_to_micro]
    type = MultiAppVariableValueSampleTransfer
    to_multi_app = micro
    execute_on = 'INITIAL TIMESTEP_END'
    source_variable = RealPhi1
    variable = phi1
  [../]
  [./phi2_to_micro]
    type = MultiAppVariableValueSampleTransfer
    to_multi_app = micro
    execute_on = 'INITIAL TIMESTEP_END'
    source_variable = RealPhi2
    variable = phi2
  [../]
#  [./J_to_micro]
#      type = MultiAppVariableValueSampleTransfer
#      multi_app = micro
#      direction = to_multiapp
#      source_variable = J
#      postprocessor = J_from_macro
#      execute_on = SAME_AS_MULTIAPP
#    [../]
#   #####################################
#   ## Cs_surface to macro
  [./cs_from_micro]
    type = MultiAppPostprocessorTransfer
    from_multi_app = micro
    execute_on = 'TIMESTEP_END'
    from_postprocessor = cs_surface
    to_postprocessor = cs_from_micro
    reduction_type = average
  [../]
  ## Cs_surface to macro
  [./soc_from_micro]
    type = MultiAppPostprocessorTransfer
    from_multi_app = micro
    execute_on = 'TIMESTEP_END'
    from_postprocessor = socp
    to_postprocessor = soc_from_micro
    reduction_type = average
  [../]
#   ###########################
#   # [./sigmaH_from_micro]
#   #   type = MultiAppVariableValueSampleTransfer
#   #   multi_app = micro
#   #   execute_on = 'TIMESTEP_END'
#   #   direction = from_multiapp
#   #   variable = SigmaH
#   #   postprocessor = SigmaH
#   #   displaced_source_mesh = false
#   #   displaced_target_mesh = false
#   #   num_points = 3
#   #   power = 2
#   #   radius = -1
#   # [../]
#   #########################
#  [./damage_from_micro]
#    type = MultiAppVariableValueSampleTransfer
#    multi_app = micro
#    execute_on = 'TIMESTEP_END'
#    direction = from_multiapp
#    variable = Damage
#    postprocessor = Damage
#    displaced_source_mesh = false
#    displaced_target_mesh = false
#    num_points = 3
#    power = 2
#    radius = -1
#  [../]
[]

and this is the one where I got the error from where I was adjusting things.

Ill check out the postprocessor outputs on the original one. Thanks!

[GiudGiud]

Task add_multi_app is not registered to build Problem derived objects

nothing in what you pasted could cause this error.

I don't think you need to have

[Problem]
  type = FEProblem
[]

in the micro.i input but i also don't think it explains the error either.

You also dont need this line

    app_type = babblerAPP

but also not an issue.

Are you passing command line arguments by any chance?
Are you combining input files?

[GiudGiud]

once you are past that error,
can you set

[Executioner]
  verbose = true
  automatic_scaling = true

...
[]

[Debug]
  show_var_residual_norms = true
[]

so we can see if there is a scaling reason for these solves to converge so little under SVD