FVBoundaryIntegralValueConstraint

This object implements the residuals that enforce the constraint

var element = document.getElementById("moose-equation-db9783b5-9690-44e2-9724-a931e9d61ec2");katex.render("\\int_{\\partial \\Omega} \\phi = \\int_{\\partial \\Omega} \\phi_0", element, {displayMode:true,throwOnError:false});

using a Lagrange multiplier approach. E.g. this object enforces the constraint that the average value of $var element = document.getElementById("moose-equation-789c38bc-a7b8-4725-bf69-b71edf294e19");katex.render("\\phi", element, {displayMode:false,throwOnError:false});$ match $var element = document.getElementById("moose-equation-52e635f7-dce6-44ba-b711-bfb4d6d722e0");katex.render("\\phi_0", element, {displayMode:false,throwOnError:false});$ on the prescribed boundary (denoted by $var element = document.getElementById("moose-equation-60a74392-68c8-4617-8af9-9a4212ac9800");katex.render("\\partial \\Omega", element, {displayMode:false,throwOnError:false});$ in the equation above). This object is the boundary version of the volumetric object FVIntegralValueConstraint.

warning

The contribution to the diagonal of the system of this kernel is null, which introduces a saddle point. Make sure to use a NONZERO shift in your preconditioner.

Example input syntax

In this example, the average value of the variable v is set on the right boundary using a FVBoundaryIntegralValueConstraint. In combination with a single Dirichlet boundary condition on the left boundary, this makes the numerical problem accept a single numerical solution, and be well-posed.

[FVBCs]
  [left]
    type = FVDirichletBC
    variable = v
    boundary = left
    value = 7
  []
  [right]
    type = FVBoundaryIntegralValueConstraint
    variable = v
    boundary = right
    phi0 = 42
    lambda = lambda
  []
[]

Input Parameters

boundaryThe list of boundary IDs from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Unit:(no unit assumed)
Controllable:No
Description:The list of boundary IDs from the mesh where this object applies
lambdaLagrange multiplier variable
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:Lagrange multiplier variable
variableThe name of the variable that this boundary condition applies to
C++ Type:NonlinearVariableName
Unit:(no unit assumed)
Controllable:No
Description:The name of the variable that this boundary condition applies to

Required Parameters

displacementsThe displacements
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:The displacements
phi00The value that the constraint will enforce.
Default:0
C++ Type:PostprocessorName
Unit:(no unit assumed)
Controllable:No
Description:The value that the constraint will enforce.
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
Unit:(no unit assumed)
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.

Optional Parameters

absolute_value_vector_tagsThe tags for the vectors this residual object should fill with the absolute value of the residual contribution
C++ Type:std::vector<TagName>
Unit:(no unit assumed)
Controllable:No
Description:The tags for the vectors this residual object should fill with the absolute value of the residual contribution
extra_matrix_tagsThe extra tags for the matrices this Kernel should fill
C++ Type:std::vector<TagName>
Unit:(no unit assumed)
Controllable:No
Description:The extra tags for the matrices this Kernel should fill
extra_vector_tagsThe extra tags for the vectors this Kernel should fill
C++ Type:std::vector<TagName>
Unit:(no unit assumed)
Controllable:No
Description:The extra tags for the vectors this Kernel should fill
matrix_tagssystemThe tag for the matrices this Kernel should fill
Default:system
C++ Type:MultiMooseEnum
Unit:(no unit assumed)
Options:nontime, system
Controllable:No
Description:The tag for the matrices this Kernel should fill
vector_tagsnontimeThe tag for the vectors this Kernel should fill
Default:nontime
C++ Type:MultiMooseEnum
Unit:(no unit assumed)
Options:nontime, time
Controllable:No
Description:The tag for the vectors this Kernel should fill

Tagging Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Unit:(no unit assumed)
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
Unit:(no unit assumed)
Controllable:Yes
Description:Set the enabled status of the MooseObject.
implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:Determines whether this object is calculated using an implicit or explicit form
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
Unit:(no unit assumed)
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

(moose/test/tests/fvkernels/fv_simple_diffusion/dirichlet-constrained-average-value.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 10
  ny = 10
[]

[Variables]
  [u]
  []
  [v]
    family = MONOMIAL
    order = CONSTANT
    fv = true
  []
  [lambda]
    family = SCALAR
    order = FIRST
  []
[]

[Kernels]
  [diff]
    type = ADDiffusion
    variable = u
  []
[]

[FVKernels]
  [diff]
    type = FVDiffusion
    variable = v
    coeff = coeff
  []
[]

[FVBCs]
  [left]
    type = FVDirichletBC
    variable = v
    boundary = left
    value = 7
  []
  [right]
    type = FVBoundaryIntegralValueConstraint
    variable = v
    boundary = right
    phi0 = 42
    lambda = lambda
  []
[]

[Materials]
  [diff]
    type = ADGenericFunctorMaterial
    prop_names = 'coeff'
    prop_values = '1'
  []
[]

[BCs]
  [left]
    type = ADDirichletBC
    variable = u
    boundary = left
    value = 7
  []
  [right]
    type = ADDirichletBC
    variable = u
    boundary = right
    value = 42
  []
[]

[Executioner]
  type = Steady
  solve_type = 'NEWTON'
  petsc_options_iname = '-pc_type -pc_factor_shift_type'
  petsc_options_value = 'lu       NONZERO'
  residual_and_jacobian_together = true
[]

[Outputs]
  exodus = true
  hide = lambda
[]

Example input syntax
Input Parameters