ScalarLMKernel

This Kernel demonstrates the usage of the scalar augmentation class described in KernelScalarBase. This single kernel is an alternative to the combination of ScalarLagrangeMultiplier, AverageValueConstraint, and an Elemental Integral Postprocessor. All terms from the spatial and scalar variables are handled by this object.

This Kernel enforces the constraint of

where is a given constant, using a Lagrange multiplier approach. Since this is a single constraint, a single scalar variable is required, as shown below.


[Variables]
  [lambda]
    family = SCALAR
    order = FIRST
  []
[]

The residual of related to the Lagrange multiplier is given as:

(1)

The residual of the Lagrange multiplier is given as:

(2)

This Kernel implements the residual and Jacobian contributions to the spatial variable equation from the in Eq. (1). Also, it implements the residual and Jacobian contributions to the scalar Lagrange multiplier constraint equation from the spatial variable in Eq. (2).

So that the input syntax matches with ScalarLagrangeMultiplier, a Postprocessor is required that computes the total volume of the domain, assigned to the parameter pp_name.

Currently, a NullScalarKernel is required to activate the dependency of the scalar variable within the block or subdomain of this object. See one of the example files listed below.

The detailed description of the derivation of the weak form can be found at scalar_constraint_kernel.

Input Parameters

  • pp_nameName of the Postprocessor containing the volume of the domain.

    C++ Type:PostprocessorName

    Controllable:No

    Description:Name of the Postprocessor containing the volume of the domain.

  • valueGiven (constant) which we want the integral of the solution variable to match.

    C++ Type:double

    Controllable:No

    Description:Given (constant) which we want the integral of the solution variable to match.

  • variableThe name of the variable that this residual object operates on

    C++ Type:NonlinearVariableName

    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>

    Controllable:No

    Description:The list of blocks (ids or names) that this object will be applied

  • compute_field_residualsTrueWhether to compute residuals for the field variable.

    Default:True

    C++ Type:bool

    Controllable:No

    Description:Whether to compute residuals for the field variable.

  • compute_scalar_residualsTrueWhether to compute scalar residuals

    Default:True

    C++ Type:bool

    Controllable:No

    Description:Whether to compute scalar residuals

  • displacementsThe displacements

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:The displacements

  • kappaPrimary coupled scalar variable

    C++ Type:std::vector<VariableName>

    Controllable:No

    Description:Primary coupled scalar variable

  • 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

    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.

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>

    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>

    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>

    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

    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

    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>

    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>

    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

    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

    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>

    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

    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

    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