VectorFunctionAux

Auxiliary Kernel that creates and updates a vector field variable by sampling a Function object, via the vectorValue method, through space and time.

Example

The VectorFunctionAux object may be used to populate a vector auxiliary variable for use with objects designed to be coupled to vector variables or for computing vector valued values such as velocity for post processing purposes.

The following partial input file shows an example of populating a vector auxiliary variable using a parsed function.

[AuxVariables]
  [vec]
    family = LAGRANGE_VEC
    order = FIRST
  []
[]

[Functions]
  [function]
    type = ParsedVectorFunction
    value_x = t*x
    value_y = t*y
  []
[]

[AuxKernels]
  [vec]
    type = VectorFunctionAux
    variable = vec
    function = function
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

Input Parameters

functionThe function to use as the value.
C++ Type:FunctionName
Options:
Description:The function to use as the value.
variableThe name of the variable that this object applies to
C++ Type:AuxVariableName
Options:
Description:The name of the variable that this object applies to

Required Parameters

blockThe list of block ids (SubdomainID) that this object will be applied
C++ Type:std::vector<SubdomainName>
Options:
Description:The list of block ids (SubdomainID) that this object will be applied
boundaryThe list of boundary IDs from the mesh where this boundary condition applies
C++ Type:std::vector<BoundaryName>
Options:
Description:The list of boundary IDs from the mesh where this boundary condition applies
check_boundary_restrictedTrueWhether to check for multiple element sides on the boundary in the case of a boundary restricted, element aux variable. Setting this to false will allow contribution to a single element's elemental value(s) from multiple boundary sides on the same element (example: when the restricted boundary exists on two or more sides of an element, such as at a corner of a mesh
Default:True
C++ Type:bool
Options:
Description:Whether to check for multiple element sides on the boundary in the case of a boundary restricted, element aux variable. Setting this to false will allow contribution to a single element's elemental value(s) from multiple boundary sides on the same element (example: when the restricted boundary exists on two or more sides of an element, such as at a corner of a mesh
execute_onLINEAR TIMESTEP_ENDThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM, PRE_DISPLACE.
Default:LINEAR TIMESTEP_END
C++ Type:ExecFlagEnum
Options:NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM, PRE_DISPLACE
Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM, PRE_DISPLACE.

Optional Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Options:
Description:Adds user-defined labels for accessing object parameters via control logic.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Options:
Description:Set the enabled status of the MooseObject.
seed0The seed for the master random number generator
Default:0
C++ Type:unsigned int
Options:
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
Options:
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

Input Files

(modules/geochemistry/test/tests/kernels/advection_1.i)
(modules/level_set/examples/vortex/vortex_supg.i)
(modules/level_set/examples/vortex/vortex.i)
(modules/level_set/test/tests/functions/olsson_vortex/olsson_vortex.i)
(test/tests/auxkernels/vector_function_aux/vector_function_aux.i)
(test/tests/kernels/vector_dot_dot/vector_test.i)
(modules/level_set/examples/vortex/vortex_reinit.i)

References

(test/tests/auxkernels/vector_function_aux/vector_function_aux.i)

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

[AuxVariables]
  [vec]
    family = LAGRANGE_VEC
    order = FIRST
  []
[]

[Variables]
  [u][]
[]

[Functions]
  [function]
    type = ParsedVectorFunction
    value_x = t*x
    value_y = t*y
  []
[]

[AuxKernels]
  [vec]
    type = VectorFunctionAux
    variable = vec
    function = function
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

[Problem]
  type = FEProblem
  #solve = false
  kernel_coverage_check = false
[]

[Executioner]
  type = Transient
  start_time = 0.0
  num_steps = 5
  dt = 1
[]

[Outputs]
  exodus = true
[]

(modules/geochemistry/test/tests/kernels/advection_1.i)

# A step-like initial concentration is advected to the right using a constant velocity.
# Because of the Dirichlet BC on the left, the step-like concentration profile is maintained (up to the usual numerical diffusion)
# Because upwinding_type=full in the ConservativeAdvection Kernel, there are no overshoots and undershoots
# The total amount of "conc" should increase by dt * velocity every timestep, as recorded by the front_position Postprocessor
[Mesh]
  type = GeneratedMesh
  dim = 1
  nx = 100
[]

[Variables]
  [conc]
  []
[]

[ICs]
  [conc]
    type = FunctionIC
    function = 'if(x<=0.25, 1, 0)'
    variable = conc
  []
[]

[BCs]
  [left]
    type = DirichletBC
    boundary = left
    value = 1.0
    variable = conc
  []
[]

[Kernels]
  [dot]
    type = GeochemistryTimeDerivative
    variable = conc
  []
  [adv]
    type = ConservativeAdvection
    velocity = velocity
    upwinding_type = full
    variable = conc
  []
[]

[AuxVariables]
  [velocity]
    family = MONOMIAL_VEC
    order = CONSTANT
  []
[]

[AuxKernels]
  [velocity]
    type = VectorFunctionAux
    function = vel_fcn
    variable = velocity
  []
[]

[Functions]
  [vel_fcn]
    type = ParsedVectorFunction
    value_x = 1
    value_y = 0
    value_z = 0
  []
[]

[Executioner]
  type = Transient
  solve_type = Newton
  dt = 0.01
  end_time = 0.1
[]

[Postprocessors]
  [front_position]
    type = ElementIntegralVariablePostprocessor
    variable = conc
  []
[]

[Outputs]
  csv = true
[]

(modules/level_set/examples/vortex/vortex_supg.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  xmax = 1
  ymax = 1
  nx = 16
  ny = 16
  uniform_refine = 2
  elem_type = QUAD9
[]

[AuxVariables]
  [./velocity]
    family = LAGRANGE_VEC
  [../]
[]

[AuxKernels]
  [./vec]
    type = VectorFunctionAux
    variable = velocity
    function = velocity_func
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

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

[Functions]
  [./phi_exact]
    type = LevelSetOlssonBubble
    epsilon = 0.01184
    center = '0.5 0.75 0'
    radius = 0.15
  [../]
  [./velocity_func]
    type = LevelSetOlssonVortex
    reverse_time = 2
  [../]
[]

[ICs]
  [./phi_ic]
    type = FunctionIC
    function = phi_exact
    variable = phi
  [../]
[]

[Kernels]
  [./time]
    type = TimeDerivative
    variable = phi
  [../]
  [./advection]
    type = LevelSetAdvection
    velocity = velocity
    variable = phi
  [../]
  [./advection_supg]
    type = LevelSetAdvectionSUPG
    velocity = velocity
    variable = phi
  [../]
  [./time_supg]
    type = LevelSetTimeDerivativeSUPG
    velocity = velocity
    variable = phi
  [../]
[]

[Postprocessors]
  [./area]
    type = LevelSetVolume
    threshold = 0.5
    variable = phi
    location = outside
    execute_on = 'initial timestep_end'
  [../]
  [./cfl]
    type = LevelSetCFLCondition
    velocity = velocity
    execute_on = 'initial timestep_end'
  [../]
[]

[Executioner]
  type = Transient
  solve_type = PJFNK
  start_time = 0
  end_time = 2
  scheme = crank-nicolson
  petsc_options_iname = '-pc_type -pc_sub_type'
  petsc_options_value = 'asm      ilu'
  [./TimeStepper]
    type = PostprocessorDT
    postprocessor = cfl
    scale = 0.8
  [../]
[]

[Outputs]
  csv = true
  exodus = true
[]

(modules/level_set/examples/vortex/vortex.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  xmax = 1
  ymax = 1
  nx = 16
  ny = 16
  uniform_refine = 2
  elem_type = QUAD9
[]

[AuxVariables]
  [./velocity]
    family = LAGRANGE_VEC
  [../]
[]

[AuxKernels]
  [./vec]
    type = VectorFunctionAux
    variable = velocity
    function = velocity_func
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

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

[Functions]
  [./phi_exact]
    type = LevelSetOlssonBubble
    epsilon = 0.01184
    center = '0.5 0.75 0'
    radius = 0.15
  [../]
  [./velocity_func]
    type = LevelSetOlssonVortex
    reverse_time = 2
  [../]
[]

[ICs]
  [./phi_ic]
    type = FunctionIC
    function = phi_exact
    variable = phi
  [../]
[]

[Kernels]
  [./time]
    type = TimeDerivative
    variable = phi
  [../]
  [./advection]
    type = LevelSetAdvection
    velocity = velocity
    variable = phi
  [../]
[]

[Postprocessors]
  [./area]
    type = LevelSetVolume
    threshold = 0.5
    variable = phi
    location = outside
    execute_on = 'initial timestep_end'
  [../]
  [./cfl]
    type = LevelSetCFLCondition
    velocity = velocity
    execute_on = 'initial timestep_end'
  [../]
[]

[Executioner]
  type = Transient
  solve_type = PJFNK
  start_time = 0
  end_time = 2
  scheme = crank-nicolson
  petsc_options_iname = '-pc_type -pc_sub_type'
  petsc_options_value = 'asm      ilu'
  [./TimeStepper]
    type = PostprocessorDT
    postprocessor = cfl
    scale = 0.8
  [../]
[]

[Outputs]
  csv = true
  exodus = true
[]

(modules/level_set/test/tests/functions/olsson_vortex/olsson_vortex.i)

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

[AuxVariables]
  [./velocity]
    family = LAGRANGE_VEC
  [../]
[]

[AuxKernels]
  [./vec]
    type = VectorFunctionAux
    variable = velocity
    function = velocity_func
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

[Functions]
  [./velocity_func]
    type = LevelSetOlssonVortex
    reverse_time = 2
  [../]
[]

[Problem]
  solve = false
[]

[Executioner]
  type = Transient
  dt = 0.1
  end_time = 2
[]

[Outputs]
  exodus = true
[]

(test/tests/auxkernels/vector_function_aux/vector_function_aux.i)

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

[AuxVariables]
  [vec]
    family = LAGRANGE_VEC
    order = FIRST
  []
[]

[Variables]
  [u][]
[]

[Functions]
  [function]
    type = ParsedVectorFunction
    value_x = t*x
    value_y = t*y
  []
[]

[AuxKernels]
  [vec]
    type = VectorFunctionAux
    variable = vec
    function = function
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

[Problem]
  type = FEProblem
  #solve = false
  kernel_coverage_check = false
[]

[Executioner]
  type = Transient
  start_time = 0.0
  num_steps = 5
  dt = 1
[]

[Outputs]
  exodus = true
[]

(test/tests/kernels/vector_dot_dot/vector_test.i)

# Tests calculation of first and second time derivative
# of a coupled vector variable in a material
# a_vec(x,y,z,t) = [t*(t*x + y), t*y, 0]
# a_vec_dot(x,y,z,t) = [2*t*x + y, y, 0]
# a_vec_dot_dot(x,y,z,t) = [2*x, 0, 0]
#
# IMPORTANT NOTE:
# Currently, this test produces a_vec_dot and a_vec_dot_dot that contains oscillations over time.
# This is a known by-product of Newmark Beta time integration (see the Newmark Beta documentation),
# but as of Summer 2019, there is no alternative time integrator in MOOSE that can dampen these
# oscillations. This test is used as coverage for the function call coupledVectorDotDot.

[Mesh]
  type = GeneratedMesh
  dim = 2
  xmin = 0
  xmax = 4
  ymin = 0
  ymax = 4
  nx = 8
  ny = 8
[]

[Functions]
  [a_fn]
    type = ParsedVectorFunction
    value_x = 't * (t * x + y)'
    value_y = 't * y'
    value_z = 0
  []
[]

[AuxVariables]
  [a]
    family = LAGRANGE_VEC
    order = FIRST
  []
[]

[AuxKernels]
  [a_ak]
    type = VectorFunctionAux
    variable = a
    function = a_fn
  []
[]

[Materials]
  [cm]
    type = VectorCoupledValuesMaterial
    variable = a
  []
[]

[Variables]
  [u]   # u is zero
    family = LAGRANGE_VEC
    order = FIRST
  []
[]

[Kernels]
  [td]
    type = VectorTimeDerivative
    variable = u
  []
[]

[Executioner]
  type = Transient
  dt = 1
  num_steps = 3

  [TimeIntegrator]
    type = NewmarkBeta
  []
[]

[Outputs]
  [./out]
    type = Exodus
    output_material_properties = true
    show_material_properties = 'a_value a_dot a_dot_dot a_dot_du a_dot_dot_du'
    execute_on = 'TIMESTEP_END'
  [../]
[]

(modules/level_set/examples/vortex/vortex_reinit.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  xmax = 1
  ymax = 1
  nx = 16
  ny = 16
  uniform_refine = 2
  elem_type = QUAD9
  second_order = true
[]

[AuxVariables]
  [./velocity]
    family = LAGRANGE_VEC
  [../]
[]

[AuxKernels]
  [./vec]
    type = VectorFunctionAux
    variable = velocity
    function = velocity_func
    execute_on = 'INITIAL TIMESTEP_END'
  [../]
[]

[Variables]
  [phi]
    family = LAGRANGE
  []
[]

[Functions]
  [phi_exact]
    type = LevelSetOlssonBubble
    epsilon = 0.03
    center = '0.5 0.75 0'
    radius = 0.15
  []
  [./velocity_func]
    type = LevelSetOlssonVortex
    reverse_time = 2
  [../]
[]

[ICs]
  [phi_ic]
    type = FunctionIC
    function = phi_exact
    variable = phi
  []
[]

[Kernels]
  [time]
    type = TimeDerivative
    variable = phi
  []
  [advection]
    type = LevelSetAdvection
    velocity = velocity
    variable = phi
  []
  [advection_supg]
    type = LevelSetAdvectionSUPG
    velocity = velocity
    variable = phi
  []
  [time_supg]
    type = LevelSetTimeDerivativeSUPG
    velocity = velocity
    variable = phi
  []
[]

[Postprocessors]
  [area]
    type = LevelSetVolume
    threshold = 0.5
    variable = phi
    location = outside
    execute_on = 'initial timestep_end'
  []
  [cfl]
    type = LevelSetCFLCondition
    velocity = velocity
    execute_on = 'initial timestep_end'
  []
[]

[Problem]
  type = LevelSetProblem
[]

[Preconditioning/smp]
    type = SMP
    full = true
[]

[Executioner]
  type = Transient
  solve_type = NEWTON
  start_time = 0
  end_time = 2
  scheme = crank-nicolson
  [TimeStepper]
    type = PostprocessorDT
    postprocessor = cfl
    scale = 0.8
  []
[]

[MultiApps]
  [reinit]
    type = LevelSetReinitializationMultiApp
    input_files = 'vortex_reinit_sub.i'
    execute_on = TIMESTEP_END
  []
[]

[Transfers]
  [to_sub]
    type = MultiAppCopyTransfer
    source_variable = phi
    variable = phi
    direction = to_multiapp
    multi_app = reinit
    execute_on = 'timestep_end'
  []

  [to_sub_init]
    type = MultiAppCopyTransfer
    source_variable = phi
    variable = phi_0
    direction = to_multiapp
    multi_app = reinit
    execute_on = 'timestep_end'
  []

  [from_sub]
    type = MultiAppCopyTransfer
    source_variable = phi
    variable = phi
    direction = from_multiapp
    multi_app = reinit
    execute_on = 'timestep_end'
  []
[]

[Outputs]
  csv = true
  exodus = true
[]

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Input Parameters
Input Files
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