CoupledForce / ADCoupledForce

Description

CoupledForce (and the AD version, ADCoupledForce) implements a source term within the domain $var element = document.getElementById("moose-equation-402a800e-a097-4e35-9418-129c246f74e1");katex.render("\\Omega", element, {displayMode:false,throwOnError:false});$ proportional to a coupled variable: $var element = document.getElementById("moose-equation-9647c831-109b-4ce1-b52f-36524332c790");katex.render("\\underbrace{-\\sigma v}_{\\textrm{CoupledForce}} + \\sum_{i=1}^n \\beta_i = 0 \\in \\Omega,", element, {displayMode:true,throwOnError:false});$ where $var element = document.getElementById("moose-equation-c462c11f-3412-45f4-a64e-2936df32c0b9");katex.render("\\sigma", element, {displayMode:false,throwOnError:false});$ is a known scalar coefficient, $var element = document.getElementById("moose-equation-c98de1b3-45f3-4252-a77a-8ee3f81c45c8");katex.render("v", element, {displayMode:false,throwOnError:false});$ is a coupled unknown value, and the second term on the left hand side corresponds to the strong forms of other kernels. In a species transport context, the value $var element = document.getElementById("moose-equation-deae8bac-ea2b-462d-9612-b00ae5b9c246");katex.render("\\sigma", element, {displayMode:false,throwOnError:false});$ can be regarded as a reaction rate coefficient.

The weak form, in inner-product notation, is defined as

$var element = document.getElementById("moose-equation-46acfcc8-acd9-47ca-9c86-91ac5c694ecd");katex.render("R_i(u_h) = (\\psi_i, -\\sigma v) \\quad \\forall \\psi_i,", element, {displayMode:true,throwOnError:false});$ where $var element = document.getElementById("moose-equation-df833b5c-00aa-43f2-9be6-e401deb63c3c");katex.render("\\psi_i", element, {displayMode:false,throwOnError:false});$ are the test functions and $var element = document.getElementById("moose-equation-385dca3c-687b-4e68-9f06-882d63d7b0c4");katex.render("u_h \\in \\mathcal{S}^h", element, {displayMode:false,throwOnError:false});$ is the finite element solution of the weak formulation.

The corresponding Jacobian (used in CoupledForce) is $var element = document.getElementById("moose-equation-0b176a5b-2a6a-43ac-a746-beedc5cc092d");katex.render("\\frac{\\partial R_i(u_h)}{\\partial u_j} = (\\psi_i, -\\sigma \\phi_j).", element, {displayMode:true,throwOnError:false});$

Example Syntax

The kernel block below shows a variable $var element = document.getElementById("moose-equation-e3cf8db0-6578-4d42-87a7-0aff85ae121d");katex.render("u", element, {displayMode:false,throwOnError:false});$ that is diffusing and being produced at a rate proportional to the concentration of a variable $var element = document.getElementById("moose-equation-c2423f47-01ff-4fe8-b5d4-9dfd68346e79");katex.render("v", element, {displayMode:false,throwOnError:false});$ which is also diffusing.

[Kernels]
  [./diff_u]
    type = Diffusion
    variable = u
  [../]

  [./coupled_force_u]
    type = CoupledForce
    variable = u
    v = v
  [../]

  [./diff_v]
    type = Diffusion
    variable = v
  [../]
[]

note

In this example the input parameter "coef" that corresponds to $var element = document.getElementById("moose-equation-4ed56f37-1e4f-46ee-93ed-6d10510800eb");katex.render("\\sigma", element, {displayMode:false,throwOnError:false});$ is omitted. In this case the "coef" value defaults to one.

note

The coupled variable "v" cannot be equal to the equation "variable" with this kernel. Use the CoefReaction kernel for this purpose.

Input Parameters

vThe coupled variable which provides the force
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:The coupled variable which provides the force
variableThe name of the variable that this residual object operates on
C++ Type:NonlinearVariableName
Unit:(no unit assumed)
Controllable:No
Description:The name of the variable that this residual object operates on

Required Parameters

blockThe list of blocks (ids or names) that this object will be applied
C++ Type:std::vector<SubdomainName>
Unit:(no unit assumed)
Controllable:No
Description:The list of blocks (ids or names) that this object will be applied
coef1Coefficent ($\sigma$) multiplier for the coupled force term.
Default:1
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Coefficent ($\sigma$) multiplier for the coupled force term.
displacementsThe displacements
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:The displacements
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.
diag_save_inThe name of auxiliary variables to save this Kernel's diagonal Jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
C++ Type:std::vector<AuxVariableName>
Unit:(no unit assumed)
Controllable:No
Description:The name of auxiliary variables to save this Kernel's diagonal Jacobian contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
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
save_inThe name of auxiliary variables to save this Kernel's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
C++ Type:std::vector<AuxVariableName>
Unit:(no unit assumed)
Controllable:No
Description:The name of auxiliary variables to save this Kernel's residual contributions to. Everything about that variable must match everything about this variable (the type, what blocks it's on, etc.)
seed0The seed for the master random number generator
Default:0
C++ Type:unsigned int
Unit:(no unit assumed)
Controllable:No
Description:The seed for the master random number generator
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/bcs/coupled_dirichlet_bc/coupled_dirichlet_bc.i)

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

[Variables]
  [./u]
    order = FIRST
    family = LAGRANGE
  [../]

  [./v]
    order = FIRST
    family = LAGRANGE
  [../]
[]

[Kernels]
  [./diff_u]
    type = Diffusion
    variable = u
  [../]

  [./coupled_force_u]
    type = CoupledForce
    variable = u
    v = v
  [../]

  [./diff_v]
    type = Diffusion
    variable = v
  [../]
[]

[BCs]
  # BCs on left
  # u: u=1
  # v: v=2
  [./left_u]
    type = DirichletBC
    variable = u
    boundary = 3
    value = 1
  [../]

  [./left_v]
    type = DirichletBC
    variable = v
    boundary = 3
    value = 2
  [../]

  # BCs on right
  # u: c*u + u^2 + v^2 = 9
  # v: no flux
  [./right_u]
    type = CoupledDirichletBC
    variable = u
    boundary = 1
    value = 9
    v=v
  [../]
[]

[Preconditioning]
  [./precond]
    type = SMP
    # 'full = true' is required for computeOffDiagJacobian() to get
    # called.  If you comment this out, you should see that this test
    # requires a different number of linear and nonlinear iterations.
    full = true
  [../]
[]

[Executioner]
  type = Steady

  # solve_type = 'PJFNK'
  solve_type = 'NEWTON'

  # Uncomment next line to disable line search.  With line search enabled, you must use full=true with Newton or else it will fail.
  # line_search = 'none'

  petsc_options_iname = '-pc_type -pc_hypre_type'
  petsc_options_value = 'hypre boomeramg'

  nl_rel_tol = 1e-10
  l_tol = 1e-12
  nl_max_its = 10
[]

[Outputs]
  file_base = out
  exodus = true
[]

Description
Example Syntax
Input Parameters