VectorNeumannBC

Imposes the integrated boundary condition $var element = document.getElementById("moose-equation-7fd0622e-de87-4f27-89b2-344dc33c31c5");katex.render("\\frac{\\partial u}{\\partial n}=\\vec{V}\\cdot\\hat{n}", element, {displayMode:false,throwOnError:false});$ , where $var element = document.getElementById("moose-equation-5294a848-ccf2-4fb9-9703-74c9d1e0090b");katex.render("\\vec{V}", element, {displayMode:false,throwOnError:false});$ is a user-defined, constant vector.

Description

VectorNeumannBC is an IntegratedBC which weakly imposes the flux boundary condition $var element = document.getElementById("moose-equation-1d207665-4e3b-43f3-ae1e-05583e06bae5");katex.render("\\frac{\\partial u}{\\partial n} = \\vec{V}\\cdot\\hat{n}", element, {displayMode:false,throwOnError:false});$ , where the user specifies the vector $var element = document.getElementById("moose-equation-62b7c16a-8e90-4791-bcd2-917493170c07");katex.render("\\vec{V}", element, {displayMode:false,throwOnError:false});$ and the unit normal vector $var element = document.getElementById("moose-equation-e9aecb42-1ad4-41bd-9b2f-1a7cdd31f4ce");katex.render("\\hat{n}", element, {displayMode:false,throwOnError:false});$ is determined by the geometry of the domain $var element = document.getElementById("moose-equation-4777cb29-c14b-4baa-af1d-a30483dc1a5c");katex.render("\\Omega", element, {displayMode:false,throwOnError:false});$ . This class is appropriate to use in systems of partial differential equations (PDEs) of the form $(1)var element = document.getElementById("moose-equation-1c54e326-539c-4fb2-af51-0c035d611b94");katex.render("\\begin{aligned} -\\nabla^2 u &= f && \\quad \\in \\Omega \\\\ u &= g && \\quad \\in \\partial \\Omega_D \\\\ \\frac{\\partial u}{\\partial n} &= \\vec{V} \\cdot \\hat{n} && \\quad \\in \\partial \\Omega_N \\end{aligned}", element, {displayMode:true,throwOnError:false});$

note

There is not a 1:1 correspondence between the choice of $var element = document.getElementById("moose-equation-2c037948-df70-4bbf-ac7e-6c4f8644f17d");katex.render("\\vec{V}", element, {displayMode:false,throwOnError:false});$ and the resulting solution, since the component of $var element = document.getElementById("moose-equation-3947572d-4aa0-4c7f-b2ea-0fb917d6c7b3");katex.render("\\vec{V}", element, {displayMode:false,throwOnError:false});$ which is orthogonal to the outward normal vector will not have any effect on the result.

This class exists mainly for convenience: if the true solution has a constant flux, then it is easier to specify Neumann boundary conditions on parts of the boundary with different outward normal vectors by simply specifying the true constant flux vector, and allowing MOOSE to dot it with the appropriate outward normals as necessary.

Example Input Syntax

  [./top]
    type = VectorNeumannBC
    variable = u
    vector_value = '1 1 0'
    boundary = 2
  [../]

Input Parameters

variableThe name of the variable that this boundary condition applies to
C++ Type:NonlinearVariableName
Description:The name of the variable that this boundary condition applies to
boundaryThe list of boundary IDs from the mesh where this boundary condition applies
C++ Type:std::vector
Description:The list of boundary IDs from the mesh where this boundary condition applies

Required Parameters

vector_value0 0 0vector this BC should act in
Default:0 0 0
C++ Type:libMesh::VectorValue
Description:vector this BC should act in

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 BC'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 BC'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 BC'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 BC'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 Input Syntax
Input Parameters