MassEigenKernel

Description

MassEigenKernel is used in the context of solving eigenvalue problems of the form

$(1)var element = document.getElementById("moose-equation-581afba6-e192-4226-a65d-6d54abb1c3fe");katex.render("\\widetilde{A}\\vec{u} = \\lambda\\widetilde{B}\\vec{u} \", element, {displayMode:true,throwOnError:false});$ where $var element = document.getElementById("moose-equation-35ec0650-2755-46fe-b6b5-0c2fc76d9bad");katex.render("\\lambda", element, {displayMode:false,throwOnError:false});$ represents the eigenvalue and $var element = document.getElementById("moose-equation-ad41e2ac-68b0-47a0-a934-5fac15acf7ea");katex.render("\\vec{u}", element, {displayMode:false,throwOnError:false});$ represents the eigenvector. Kernels that inherit from EigenKernel like MassEigenKernel are grouped into the $var element = document.getElementById("moose-equation-e3c132e7-a8e0-4c52-888d-69d58caf1da2");katex.render("\\widetilde{B}\\vec{u}", element, {displayMode:false,throwOnError:false});$ term and have their residual contributions multipled by the eigenvalue $var element = document.getElementById("moose-equation-1e1cffc0-3698-4cfa-a7c7-0ad35cbd8134");katex.render("\\lambda", element, {displayMode:false,throwOnError:false});$ . Consider the equation below

$(2)var element = document.getElementById("moose-equation-2ff31eca-e3ee-480d-a933-988fb575f9e1");katex.render("-\\nabla^2 u + ku = \\underbrace{\\lambda u}_{\\textrm{MassEigenKernel}} \", element, {displayMode:true,throwOnError:false});$ where $var element = document.getElementById("moose-equation-4def40e4-8038-4262-b507-07a3120ff0fd");katex.render("k", element, {displayMode:false,throwOnError:false});$ is some reaction coefficient that accounts for loss of $var element = document.getElementById("moose-equation-8b0d8587-c2d3-4b33-82ad-4f32e6a100bd");katex.render("u", element, {displayMode:false,throwOnError:false});$ . The terms on the LHS of Eq. 2 are equivalent to the LHS of Eq. 1 and similarly for the right hand sides.

Example Syntax

The kernels describing Eq. 2 are shown in the Kernel block below


[AuxKernels]
  [./x_disp]
    type = FunctionAux
    variable = x_disp
    function = x_disp_func
  [../]
  [./y_disp]
    type = FunctionAux
    variable = y_disp
    function = y_disp_func
  [../]
[]

The syntax for MassEigenKernel is simple, taking only its type and the variable that the kernel acts on.

Input Parameters

variableThe name of the variable that this Kernel operates on
C++ Type:NonlinearVariableName
Description:The name of the variable that this Kernel operates on

Required Parameters

eigen_postprocessor1The name of the postprocessor that provides the eigenvalue.
Default:1
C++ Type:PostprocessorName
Description:The name of the postprocessor that provides the eigenvalue.
eigenTrueUse for eigenvalue problem (true) or source problem (false)
Default:True
C++ Type:bool
Description:Use for eigenvalue problem (true) or source problem (false)
blockThe list of block ids (SubdomainID) that this object will be applied
C++ Type:std::vector
Description:The list of block ids (SubdomainID) that this object will be applied

Optional Parameters

enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Description:Set the enabled status of the MooseObject.
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
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.)
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
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.
control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector
Description:Adds user-defined labels for accessing object parameters via control logic.
seed0The seed for the master random number generator
Default:0
C++ Type:unsigned int
Description:The seed for the master random number generator
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
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.)
implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True
C++ Type:bool
Description:Determines whether this object is calculated using an implicit or explicit form

Advanced Parameters

vector_tagsnontimeThe tag for the vectors this Kernel should fill
Default:nontime
C++ Type:MultiMooseEnum
Description:The tag for the vectors this Kernel should fill
extra_vector_tagsThe extra tags for the vectors this Kernel should fill
C++ Type:std::vector
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
Description:The tag for the matrices this Kernel should fill
extra_matrix_tagsThe extra tags for the matrices this Kernel should fill
C++ Type:std::vector
Description:The extra tags for the matrices this Kernel should fill

Tagging Parameters

Description
Example Syntax
Input Parameters