MultiAppNearestNodeTransfer

Transfer the value to the target domain from the nearest node in the source domain.

The projection mapping may be cached at the first execution of the transfer for better performance in later executions using the "fixed_meshes" parameter. This is incompatible with adaptivity and refinement of the mesh.

Example Input File Syntax

The following examples demonstrate the use the MultiAppNearestNodeTransfer for transferring data to (Listing 1) and from (Listing 2) sub-applications.

Listing 1: Example use of MultiAppNearestNodeTransfer for transferring data to sub-applications.

[Transfers]
  [to_sub_nodal_to_nodal]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u
    variable = nodal_source_from_parent_nodal
  []
  [to_sub_nodal_to_elemental]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u
    variable = nodal_source_from_parent_elemental
  []
  [to_sub_elemental_to_nodal]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_parent_nodal
  []
  [to_sub_elemental_to_elemental]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_parent_elemental
  []
[]

Listing 2: Example use of MultiAppNearestNodeTransfer for transferring data from sub-applications.

[Transfers]
  [from_sub_nodal_from_nodal]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u
    variable = nodal_source_from_sub_nodal
  []
  [from_sub_nodal_from_elemental]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u
    variable = nodal_source_from_sub_elemental
  []
  [from_sub_elemental_from_nodal]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_sub_nodal
  []
  [from_sub_elemental_from_elemental]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_sub_elemental
  []
[]

Input Parameters

source_variableThe variable to transfer from.
C++ Type:std::vector<VariableName>
Controllable:No
Description:The variable to transfer from.
variableThe auxiliary variable to store the transferred values in.
C++ Type:std::vector<AuxVariableName>
Controllable:No
Description:The auxiliary variable to store the transferred values in.

Required Parameters

bbox_factor1Multiply bounding box width (in all directions) by the prescribed factor. Values less than 1 will shrink the bounding box; values greater than 1 will enlarge the bounding box. It is generally not advised to ever shrink the bounding box. On the other hand it may be helpful to enlarge the bounding box. Larger bounding boxes will lead to more accurate determination of the closest node/element with the tradeoff of more communication.
Default:1
C++ Type:double
Controllable:No
Description:Multiply bounding box width (in all directions) by the prescribed factor. Values less than 1 will shrink the bounding box; values greater than 1 will enlarge the bounding box. It is generally not advised to ever shrink the bounding box. On the other hand it may be helpful to enlarge the bounding box. Larger bounding boxes will lead to more accurate determination of the closest node/element with the tradeoff of more communication.
check_multiapp_execute_onTrueWhen false the check between the multiapp and transfer execute on flags is not preformed.
Default:True
C++ Type:bool
Controllable:No
Description:When false the check between the multiapp and transfer execute on flags is not preformed.
displaced_source_meshFalseWhether or not to use the displaced mesh for the source mesh.
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to use the displaced mesh for the source mesh.
displaced_target_meshFalseWhether or not to use the displaced mesh for the target mesh.
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to use the displaced mesh for the target mesh.
execute_onSAME_AS_MULTIAPPThe 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, SAME_AS_MULTIAPP, ALWAYS.
Default:SAME_AS_MULTIAPP
C++ Type:ExecFlagEnum
Options:NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM, SAME_AS_MULTIAPP, ALWAYS
Controllable:No
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, SAME_AS_MULTIAPP, ALWAYS.
fixed_meshesFalseSet to true when the meshes are not changing (ie, no movement or adaptivity). This will cache nearest node neighbors to greatly speed up the transfer.
Default:False
C++ Type:bool
Controllable:No
Description:Set to true when the meshes are not changing (ie, no movement or adaptivity). This will cache nearest node neighbors to greatly speed up the transfer.
from_multi_appThe name of the MultiApp to receive data from
C++ Type:MultiAppName
Controllable:No
Description:The name of the MultiApp to receive data from
from_solution_tagThe tag of the solution vector to be transferred (default to the solution)
C++ Type:TagName
Controllable:No
Description:The tag of the solution vector to be transferred (default to the solution)
source_boundaryThe boundary we are transferring from (if not specified, whole domain is used).
C++ Type:BoundaryName
Controllable:No
Description:The boundary we are transferring from (if not specified, whole domain is used).
target_boundaryThe boundary we are transferring to (if not specified, whole domain is used).
C++ Type:std::vector<BoundaryName>
Controllable:No
Description:The boundary we are transferring to (if not specified, whole domain is used).
to_multi_appThe name of the MultiApp to transfer the data to
C++ Type:MultiAppName
Controllable:No
Description:The name of the MultiApp to transfer the data to
to_solution_tagThe tag of the solution vector to be transferred to (default to the solution)
C++ Type:TagName
Controllable:No
Description:The tag of the solution vector to be transferred to (default to the solution)

Optional Parameters

_called_legacy_paramsTrue
Default:True
C++ Type:bool
Controllable:No
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.
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:Yes
Description:Set the enabled status of the MooseObject.
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

allow_skipped_adjustmentFalseIf set to true, the transfer skips adjustment when from or to postprocessor values are either zero or have different signs. If set to false, an error is thrown when encountering these conditions.
Default:False
C++ Type:bool
Controllable:No
Description:If set to true, the transfer skips adjustment when from or to postprocessor values are either zero or have different signs. If set to false, an error is thrown when encountering these conditions.
from_postprocessors_to_be_preservedThe name of the Postprocessor in the from-app to evaluate an adjusting factor.
C++ Type:std::vector<PostprocessorName>
Controllable:No
Description:The name of the Postprocessor in the from-app to evaluate an adjusting factor.
to_postprocessors_to_be_preservedThe name of the Postprocessor in the to-app to evaluate an adjusting factor.
C++ Type:std::vector<PostprocessorName>
Controllable:No
Description:The name of the Postprocessor in the to-app to evaluate an adjusting factor.

Conservative Transfer Parameters

(../../../SoftwareDownloads/moose/test/tests/transfers/multiapp_nearest_node_transfer/tosub_parent.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 10
  ny = 10
  elem_type = QUAD8
[]

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

[Kernels]
  [diff]
    type = Diffusion
    variable = u
  []
[]

[AuxVariables]
  [u_elemental]
    family = MONOMIAL
    order = CONSTANT
  []
[]

[AuxKernels]
  [fun_aux]
    type = FunctionAux
    function = 'x + y'
    variable = u_elemental
  []
[]

[BCs]
  [left]
    type = DirichletBC
    variable = u
    boundary = left
    value = 0
  []
  [right]
    type = DirichletBC
    variable = u
    boundary = right
    value = 1
  []
[]

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

  solve_type = 'PJFNK'

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

[Outputs]
  exodus = true
[]

[MultiApps]
  [sub]
    type = TransientMultiApp
    app_type = MooseTestApp
    execute_on = timestep_end
    positions = '0.48 0.01 0'
    input_files = tosub_sub.i
  []
[]

[Transfers]
  [to_sub_nodal_to_nodal]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u
    variable = nodal_source_from_parent_nodal
  []
  [to_sub_nodal_to_elemental]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u
    variable = nodal_source_from_parent_elemental
  []
  [to_sub_elemental_to_nodal]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_parent_nodal
  []
  [to_sub_elemental_to_elemental]
    type = MultiAppNearestNodeTransfer
    to_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_parent_elemental
  []
[]

(../../../SoftwareDownloads/moose/test/tests/transfers/multiapp_nearest_node_transfer/fromsub_parent.i)

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 10
  ny = 10
  elem_type = QUAD8
[]

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

[Kernels]
  [diff]
    type = Diffusion
    variable = u
  []
[]

[AuxVariables]
  [nodal_source_from_sub_nodal]
    family = LAGRANGE
    order = FIRST
  []
  [nodal_source_from_sub_elemental]
    family = MONOMIAL
    order = CONSTANT
  []
  [elemental_source_from_sub_nodal]
    family = LAGRANGE
    order = FIRST
  []
  [elemental_source_from_sub_elemental]
    family = MONOMIAL
    order = CONSTANT
  []
[]

[BCs]
  [left]
    type = DirichletBC
    variable = u
    boundary = left
    value = 0
  []
  [right]
    type = DirichletBC
    variable = u
    boundary = right
    value = 1
  []
[]

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

  solve_type = 'PJFNK'

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

[Outputs]
  exodus = true
[]

[MultiApps]
  [sub]
    type = TransientMultiApp
    app_type = MooseTestApp
    positions = '0.48 0.01 0 -1.01 0.01 0'
    input_files = fromsub_sub.i
  []
[]

[Transfers]
  [from_sub_nodal_from_nodal]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u
    variable = nodal_source_from_sub_nodal
  []
  [from_sub_nodal_from_elemental]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u
    variable = nodal_source_from_sub_elemental
  []
  [from_sub_elemental_from_nodal]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_sub_nodal
  []
  [from_sub_elemental_from_elemental]
    type = MultiAppNearestNodeTransfer
    from_multi_app = sub
    source_variable = u_elemental
    variable = elemental_source_from_sub_elemental
  []
[]

Example Input File Syntax
Input Parameters