Defining material properties using image stacks

[keassyguang]

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Question

Hello MOOSE Developer,

I want to use the image to describe the illumination from the UV light for a 3D printing process simulation, as shown in the figure below. The image is used to show the areas that will be irradiated. The light intensities at the irradiated areas are set to maximum light intensity and at the non-irradiated areas are set to 0. Due to the attenuation effect, the light intensity below the top surface is described by an exponential function. Different images for different layers. So there will be one set of images for the whole simulation.

I need to calculate the light intensity of each quadrature point for the activated elements. Besides, the light intensity at the quadrature points that are far away from the top surface of the current printed layer can be directly set to 0 to reduce the computational cost. To achieve this, I think I need to develop a user object using image-based functions or classes. What class or function might be helpful? Thanks a lot

[GiudGiud]

Hello

you may be able to use the ray tracing module for this?
https://mooseframework.inl.gov/modules/ray_tracing/index.html

[keassyguang]

I changed the time values so there should be no conflicts now, but I got the same results as before. Below is the modified section of the input file.

[Controls]
  # turn on/off light with image 1 pattern
  [times_image_1_on]
    type = TimePeriod
    start_time = '0'
    end_time = '1.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_1_off]
    type = TimePeriod
    start_time = '2'
    end_time = '6'
    disable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []

  # turn on/off light with image 2 pattern
  [times_image_2_on]
    type = TimePeriod
    start_time = '3'
    end_time = '4.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_2_off]
    type = TimePeriod
    start_time = '0 5'
    end_time = '2.9999 6'
    disable_objects = 'AuxKernels::LightIntensity_layer_2 AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
[]

[GiudGiud]

You changed the end times to prevent round off concerns. You did not change the start times

[keassyguang]

I also have tried setting the start time to 0.001 or -0.001, but all results were the same.

Case 1:

[Controls]
  # turn on/off light with image 1 pattern
  [times_image_1_on]
    type = TimePeriod
    start_time = '0.001'                                               # this line is modified
    end_time = '1.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_1_off]
    type = TimePeriod
    start_time = '2'
    end_time = '6'
    disable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []

  # turn on/off light with image 2 pattern
  [times_image_2_on]
    type = TimePeriod
    start_time = '3'
    end_time = '4.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_2_off]
    type = TimePeriod
    start_time = '0 5'
    end_time = '2.9999 6'
    disable_objects = 'AuxKernels::LightIntensity_layer_2 AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
[]

Case 2:

[Controls]
  # turn on/off light with image 1 pattern
  [times_image_1_on]
    type = TimePeriod
    start_time = '-0.001'                                             # this line is modified
    end_time = '1.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_1_off]
    type = TimePeriod
    start_time = '2'
    end_time = '6'
    disable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []

  # turn on/off light with image 2 pattern
  [times_image_2_on]
    type = TimePeriod
    start_time = '3'
    end_time = '4.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_2_off]
    type = TimePeriod
    start_time = '0 5'
    end_time = '2.9999 6'
    disable_objects = 'AuxKernels::LightIntensity_layer_2 AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
[]

Case 3:

[Controls]
  # turn on/off light with image 1 pattern
  [times_image_1_on]
    type = TimePeriod
    start_time = '0.001'                                               # this line is modified
    end_time = '1.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_1_off]
    type = TimePeriod
    start_time = '2'
    end_time = '6'
    disable_objects = 'AuxKernels::LightIntensity_layer_1'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []

  # turn on/off light with image 2 pattern
  [times_image_2_on]
    type = TimePeriod
    start_time = '3'
    end_time = '4.9999'
    enable_objects = 'AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
  [times_image_2_off]
    type = TimePeriod
    start_time = '-0.001 5'                                           # this line is modified
    end_time = '2.9999 6'
    disable_objects = 'AuxKernels::LightIntensity_layer_2 AuxKernels::LightIntensity_layer_2'
    execute_on = 'INITIAL TIMESTEP_BEGIN'
    reverse_on_false = false
  []
[]

[GiudGiud]

I think for just these two objects you should be able to work with reverse_on_false = true

the inputs look fine, and the logic is very simple..
Maybe remove execute_on = 'INITIAL TIMESTEP_BEGIN' from the controls. the default should work fine?

[keassyguang]

Maybe remove execute_on = 'INITIAL TIMESTEP_BEGIN' from the controls. the default should work fine?

The results are the same as previous. This might be a bug.