Is there a PostProcessor/Output object that can show a variable value along a boundary?

[richmondodufisan]

Hi,

I have a problem with a periodic solution.

When I get the simulation output, my current workflow is to take the exodus file to paraview and draw a line over the mesh to get a plot of the result, which is harmonic, and then fit it to a decaying sine function to get the properties I need. I would like to automate this process as I want to run this simulation several times for various material properties.

Is there a postprocessor object that can output the results along a boundary in excel? I browsed through the postprocessor list and I'm not sure I could find one. The only option I could think of is to use PointValue, but that would require selecting hundreds of points to keep the resolution of the sine wave good. Is there any other option for doing this?

[GiudGiud]

Hello

You could specify a line along the boundary if it is straight
https://mooseframework.inl.gov/source/vectorpostprocessors/LineValueSampler.html
this can also work
https://mooseframework.inl.gov/source/vectorpostprocessors/PositionsFunctorValueSampler.html
but you ll need to create a Positions object for the boundary. I d like that in MOOSE btw

If not you could make a new one, a BoundaryValueSampler

[GiudGiud]

You would have to have multiple CSV outputs objects. Or have multiple flags on one

CSV output does not happen unless the flag is present in the outputs block

[GiudGiud]

It does have a global effect, in that it affects all the VPPs.

[richmondodufisan]

I'm sorry I am a bit confused by what you mean. As an example, say I have:

[Postprocessors]
  [displace_y_real]
    type = PointValue
    variable = disp_y_real
    point = '0.002 0.001 0'
  []
  
  [displace_y_imag]
    type = PointValue
    variable = disp_y_imag
    point = '0.002 0.001 0'
  []
[]

[VectorPostprocessors]
  [wave_profile]
    type = LineValueSampler
    variable = disp_y
    start_point = '0.002 ${mid_height} 0'
    end_point = '${fparse l_plate - 0.002} ${mid_height} 0'
    num_points = ${number_of_points}
    sort_by = x
    execute_on = final
  []
[]

If I understand correctly, I need to do:

[Outputs]
  print_linear_residuals = false
  [csv]
    type = CSV
    execute_on = FINAL
  []
  exodus = true
  [pgraph]
    type = PerfGraphOutput
    execute_on = 'final'  # Default is "final"
    level = 1             # Default is 1
  []
[]

for the VectorPostProcessor to work, right? What about the PostProcessor?

[GiudGiud]

postprocessor will only output on final if you do this
you could do this

[Outputs]
  print_linear_residuals = false
  [csv]
    type = CSV
    execute_on = 'TIMESTEP_END FINAL'
  []

[richmondodufisan]

okay thank you