SpecifiedViewFactor

Description

This ViewFactorBase object gets view factors specified directly in the input file.

Normalization

The normalization options below are provided via "normalization_method". Denoting the original, unormalized view factors as $var element = document.getElementById("moose-equation-56bf2007-f9e9-45f7-9c71-1330030f2e4a");katex.render("\\tilde{F}_{i,j}", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ ,

lagrange_multiplier:
First the following linear system is solved:
$var element = document.getElementById("moose-equation-85ebf881-a72f-4e48-a99e-80159f036331");katex.render("\\mathbf{A} \\mathbf{x} = \\mathbf{b}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ $var element = document.getElementById("moose-equation-0d0e8f36-0f08-4b4a-892e-dd0fbe5e97f8");katex.render("A_{i,j} = \\left\\{\\begin{array}{l l} -\\frac{\\gamma_{j,i}}{C_{j,i}}& j < i\\\\ -\\frac{1}{2} - \\sum\\limits_{j=1}^{i-1} \\frac{\\gamma_{j,i}^2}{C_{j,i}} - \\sum\\limits_{j=i+1}^N \\frac{1}{C_{i,j}} & j = i\\\\ -\\frac{\\gamma_{i,j}}{C_{i,j}} & j > i\\\\ \\end{array}\\right.", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ $var element = document.getElementById("moose-equation-ea7cd32e-7a66-40e0-a8f8-7f398c7e2e06");katex.render("b_i = 1 - \\sum\\limits_j \\tilde{F}_{i,j} - \\sum\\limits_{j=1}^{i-1} \\gamma_{j,i} e_{j,i} \\left(1 - \\frac{\\gamma_{j,i}^2}{1 + \\gamma_{j,i}^2}\\right) + \\sum\\limits_{j=i+1}^N \\frac{\\gamma_{i,j}^2 e_{i,j}}{1 + \\gamma_{i,j}^2}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$
The area ratio is defined as
$var element = document.getElementById("moose-equation-7eb6653c-33f5-441b-94e4-c8fcaa98e102");katex.render("\\gamma_{i,j} = \\frac{A_i}{A_j}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$
The reciprocity deviation is defined as
$var element = document.getElementById("moose-equation-1388733d-dcb1-425a-b2b2-1b22cc2f5488");katex.render("e_{i,j} = \\tilde{F}_{i,j} - \\frac{A_j}{A_i} \\tilde{F}_{j,i}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$
The quantity $var element = document.getElementById("moose-equation-ea8dfad6-e93f-4176-bd54-b1ae0fc51582");katex.render("C_{i,j}", element, {displayMode:false,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ is defined as
$var element = document.getElementById("moose-equation-85dbc4f4-2819-4c72-aa10-48b47bb44ba2");katex.render("C_{i,j} = 2 (1 + \\gamma_{i,j}^2)", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$
Then the following corrections are applied:
$var element = document.getElementById("moose-equation-968520ea-39b6-4b1d-99ab-65dd39b2027d");katex.render("\\delta_{i,j} = \\left\\{\\begin{array}{l l} -\\frac{1}{2} x_i & j = i\\\\ -\\frac{\\left(x_i + x_j \\gamma_{i,j} + 2 \\gamma_{i,j}^2 e_{i,j}\\right)}{C_{i,j}} & j \\ne i\\\\ \\end{array}\\right.", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$ $var element = document.getElementById("moose-equation-84a48116-9630-48d6-ab21-2cd008347571");katex.render("F_{i,j} = \\tilde{F}_{i,j} + \\delta_{i,j}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$
inverse_row_sum:
This method enforces the summation rule without consideration of the reciprocity rule for enclosures:
$var element = document.getElementById("moose-equation-4dd0e3fd-64e4-4ab6-b5ca-a7bcb9f53cb2");katex.render("F_{i,j} = \\frac{\\tilde{F}_{i,j}}{\\sum\\limits_k \\tilde{F}_{k,j}}", element, {displayMode:true,throwOnError:false,macros:{"\\eqc":"\\,,","\\eqp":"\\,.","\\pd":"\\frac{\\partial #1}{\\partial #2}","\\pr":"\\left(#1\\right)","\\ddt":"\\frac{d #1}{d t}"}});$

Input Parameters

boundaryThe list of boundary IDs from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The list of boundary IDs from the mesh where this object applies
view_factorsThe view factors from sideset i to sideset j.
C++ Type:std::vector<std::vector<double>>
Unit:(no unit assumed)
Controllable:No
Description:The view factors from sideset i to sideset j.

Required Parameters

normalization_methodlagrange_multiplierNormalization method to use if 'normalize_view_factor' is 'true'.
Default:lagrange_multiplier
C++ Type:MooseEnum
Options:lagrange_multiplier, inverse_row_sum
Controllable:No
Description:Normalization method to use if 'normalize_view_factor' is 'true'.
normalize_view_factorTrueDetermines if view factors are normalized to sum to one (consistent with their definition).
Default:True
C++ Type:bool
Controllable:No
Description:Determines if view factors are normalized to sum to one (consistent with their definition).
print_view_factor_infoFalseFlag to print information about computed view factors.
Default:False
C++ Type:bool
Controllable:No
Description:Flag to print information about computed view factors.
view_factor_tol1.79769e+308Tolerance for checking view factors. Default is to allow everything.
Default:1.79769e+308
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Tolerance for checking view factors. Default is to allow everything.

Optional Parameters

allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
Default:False
C++ Type:bool
Controllable:No
Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Options:XFEM_MARK, FORWARD, ADJOINT, HOMOGENEOUS_FORWARD, ADJOINT_TIMESTEP_BEGIN, ADJOINT_TIMESTEP_END, NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, FINAL, CUSTOM, TRANSFER
Controllable:No
Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.
execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
Default:0
C++ Type:int
Controllable:No
Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.
force_postauxFalseForces the UserObject to be executed in POSTAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in POSTAUX
force_preauxFalseForces the UserObject to be executed in PREAUX
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREAUX
force_preicFalseForces the UserObject to be executed in PREIC during initial setup
Default:False
C++ Type:bool
Controllable:No
Description:Forces the UserObject to be executed in PREIC during initial setup

Execution Scheduling Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Controllable:No
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:Yes
Description:Set the enabled status of the MooseObject.
use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Advanced Parameters

prop_getter_suffixAn optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
C++ Type:MaterialPropertyName
Unit:(no unit assumed)
Controllable:No
Description:An optional suffix parameter that can be appended to any attempt to retrieve/get material properties. The suffix will be prepended with a '_' character.
use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.
Default:False
C++ Type:bool
Controllable:No
Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

Material Property Retrieval Parameters

Input Files

(modules/heat_transfer/test/tests/gray_lambert_radiator/gray_lambert_cavity.i)

(modules/heat_transfer/test/tests/gray_lambert_radiator/gray_lambert_cavity.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  xmin = 0
  xmax = 1
  ymin = 0
  ymax = 2
  nx = 1
  ny = 1
[]

[Problem]
  kernel_coverage_check = false
[]

[Variables]
  [./temperature]
    initial_condition = 300
  [../]
[]

[UserObjects]
  [view_factors_uo]
    type = SpecifiedViewFactor
    boundary = 'bottom top left right'
    view_factors = '0 0.123 0.6928 0.1841;
                    0.123 0 0.1841 0.6928;
                    0.2771 0.0736 0.4458 0.2035;
                    0.0736 0.2771 0.2035 0.4458'
    normalize_view_factor = true
    normalization_method = inverse_row_sum
    view_factor_tol = 0.05
    # Without changing from 'TIMESTEP_END' to 'INITIAL' here, this test would
    # diff, since GrayLambertSurfaceRadiationBase objects currently set their
    # view factors in initial() (and finalize() of this view factor object has
    # not yet executed). See https://github.com/idaholab/moose/issues/32611.
    # Alternatively we can keep 'TIMESTEP_END' and do 'execution_order_group = -1'.
    execute_on = 'INITIAL'
  []
  [./gray_lambert]
    type = ViewFactorObjectSurfaceRadiation
    boundary = 'bottom top left right'
    fixed_temperature_boundary = 'bottom top'
    fixed_boundary_temperatures = '550 300'
    adiabatic_boundary = 'right left'
    emissivity = '1 0.75 0.75 0.75'
    temperature = temperature
    view_factor_object_name = view_factors_uo
  [../]
[]

[VectorPostprocessors]
  [./lambert_vpp]
    type = SurfaceRadiationVectorPostprocessor
    surface_radiation_object_name = gray_lambert
    information = 'temperature emissivity radiosity heat_flux_density'
  [../]

  [./view_factors]
    type = ViewFactorVectorPostprocessor
    view_factor_object_name = view_factors_uo
  [../]
[]

[Postprocessors]
  [./heat_flux_density_bottom]
    type = GrayLambertSurfaceRadiationPP
    surface_radiation_object_name = gray_lambert
    return_type = HEAT_FLUX_DENSITY
    boundary = bottom
  [../]

  [./temperature_left]
    type = GrayLambertSurfaceRadiationPP
    surface_radiation_object_name = gray_lambert
    return_type = TEMPERATURE
    boundary = left
  [../]

  [./temperature_right]
    type = GrayLambertSurfaceRadiationPP
    surface_radiation_object_name = gray_lambert
    return_type = TEMPERATURE
    boundary = right
  [../]

  [./brightness_top]
    type = GrayLambertSurfaceRadiationPP
    surface_radiation_object_name = gray_lambert
    return_type = RADIOSITY
    boundary = top
  [../]
[]

[Executioner]
  type = Transient
  num_steps = 1
[]

Description
Normalization
Input Parameters
Input Files