TricrystalTripleJunctionIC

Tricrystal with a triple junction

Overview

This initial condition (ICs) sets the variable values to represent a grain structure with three grains coming together at a triple junction. The initial triple junction angles are set by the user.

Note that the grains are created with sharp interfaces.

Example Input File Syntax

[GlobalParams]
  # Parameters used by several kernels that are defined globally to simplify input file
  op_num = 3 # Number of order parameters used
  var_name_base = gr # base name of grains
  v = 'gr0 gr1 gr2' # Names of the grains
  theta1 = 135 # Angle the first grain makes at the triple junction
  theta2 = 100 # Angle the second grain makes at the triple junction
  length_scale = 1.0e-9 # Length scale in nm
  time_scale = 1.0e-9 # Time scale in ns
[]

[ICs]
  [gr0_IC]
    type = TricrystalTripleJunctionIC
    variable = gr0
    op_index = 1
  []
  [gr1_IC]
    type = TricrystalTripleJunctionIC
    variable = gr1
    op_index = 2
  []
  [gr2_IC]
    type = TricrystalTripleJunctionIC
    variable = gr2
    op_index = 3
  []
[]

Input Parameters

op_indexIndex for the current grain order parameter
C++ Type:unsigned int
Unit:(no unit assumed)
Controllable:No
Description:Index for the current grain order parameter
op_numNumber of grain order parameters
C++ Type:unsigned int
Unit:(no unit assumed)
Controllable:No
Description:Number of grain order parameters
variableThe variable this initial condition is supposed to provide values for.
C++ Type:VariableName
Unit:(no unit assumed)
Controllable:No
Description:The variable this initial condition is supposed to provide values for.

Required Parameters

blockThe list of blocks (ids or names) that this object will be applied
C++ Type:std::vector<SubdomainName>
Unit:(no unit assumed)
Controllable:No
Description:The list of blocks (ids or names) that this object will be applied
boundaryThe list of boundaries (ids or names) from the mesh where this object applies
C++ Type:std::vector<BoundaryName>
Unit:(no unit assumed)
Controllable:No
Description:The list of boundaries (ids or names) from the mesh where this object applies
junctionThe point where the triple junction is located. Default is the center of the mesh
C++ Type:libMesh::Point
Unit:(no unit assumed)
Controllable:No
Description:The point where the triple junction is located. Default is the center of the mesh
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
Unit:(no unit assumed)
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.
stateCURRENTThis parameter is used to set old state solutions at the start of simulation. If specifying multiple states at the start of simulation, use one IC object for each state being specified. The states are CURRENT=0 OLD=1 OLDER=2. States older than 2 are not currently supported. When the user only specifies current state, the solution is copied to the old and older states, as expected. This functionality is mainly used for dynamic simulations with explicit time integration schemes, where old solution states are used in the velocity and acceleration approximations.
Default:CURRENT
C++ Type:MooseEnum
Unit:(no unit assumed)
Options:CURRENT, OLD, OLDER
Controllable:No
Description:This parameter is used to set old state solutions at the start of simulation. If specifying multiple states at the start of simulation, use one IC object for each state being specified. The states are CURRENT=0 OLD=1 OLDER=2. States older than 2 are not currently supported. When the user only specifies current state, the solution is copied to the old and older states, as expected. This functionality is mainly used for dynamic simulations with explicit time integration schemes, where old solution states are used in the velocity and acceleration approximations.
theta1135Angle of first grain at triple junction in degrees
Default:135
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Angle of first grain at triple junction in degrees
theta2135Angle of second grain at triple junction in degrees
Default:135
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Angle of second grain at triple junction in degrees
use_interpolated_stateFalseFor the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:For the old and older state use projected material properties interpolated at the quadrature points. To set up projection use the ProjectedStatefulMaterialStorageAction.

Optional Parameters

control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector<std::string>
Unit:(no unit assumed)
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
Unit:(no unit assumed)
Controllable:No
Description:Set the enabled status of the MooseObject.
ignore_uo_dependencyFalseWhen set to true, a UserObject retrieved by this IC will not be executed before the this IC
Default:False
C++ Type:bool
Unit:(no unit assumed)
Controllable:No
Description:When set to true, a UserObject retrieved by this IC will not be executed before the this IC

Advanced Parameters

(moose/modules/phase_field/test/tests/initial_conditions/TricrystalTripleJunctionIC.i)

# This simulation tests the TricrystalTripleJunctionIC

[Mesh]
  # Mesh block. Meshes can be read in or automatically generated.
  type = GeneratedMesh
  dim = 2 # Problem dimension
  nx = 11 # Number of elements in the x direction
  ny = 11 # Number of elements in the y direction
  xmax = 1001 # Maximum x-coordinate of mesh
  xmin = 0 # Minimum x-coordinate of mesh
  ymax = 1001 # Maximum y-coordinate of mesh
  ymin = 0 # Minimum y-coordinate of mesh
  elem_type = QUAD4 # Type of elements used in the mesh
  uniform_refine = 3
[]

[GlobalParams]
  # Parameters used by several kernels that are defined globally to simplify input file
  op_num = 3 # Number of order parameters used
  var_name_base = gr # base name of grains
  v = 'gr0 gr1 gr2' # Names of the grains
  theta1 = 135 # Angle the first grain makes at the triple junction
  theta2 = 100 # Angle the second grain makes at the triple junction
  length_scale = 1.0e-9 # Length scale in nm
  time_scale = 1.0e-9 # Time scale in ns
[]

[Variables]
  [gr0]
  []
  [gr1]
  []
  [gr2]
  []
[]

[ICs]
  [gr0_IC]
    type = TricrystalTripleJunctionIC
    variable = gr0
    op_index = 1
  []
  [gr1_IC]
    type = TricrystalTripleJunctionIC
    variable = gr1
    op_index = 2
  []
  [gr2_IC]
    type = TricrystalTripleJunctionIC
    variable = gr2
    op_index = 3
  []
[]

[AuxVariables]
  [bnds]
    # Variable used to visualize the grain boundaries in the simulation
    order = FIRST
    family = LAGRANGE
  []
[]

[Kernels]
  # Kernels block where the kernels defining the residual equations are set up
  [PolycrystalKernel]
    # Custom action creating all necessary kernels for grain growth.  All input parameters are up in GlobalParams
  []
[]

[AuxKernels]
  # AuxKernel block, defining the equations used to calculate the auxvars
  [bnds_aux]
    # AuxKernel that calculates the GB term
    type = BndsCalcAux
    variable = bnds
    execute_on = 'initial timestep_end'
  []
[]

[Materials]
  [material]
    # Material properties
    type = GBEvolution
    T = 450 # Constant temperature of the simulation (for mobility calculation)
    wGB = 14 # Width of the diffuse GB
    GBmob0 = 2.5e-6 #m^4(Js) for copper from schonfelder1997molecular bibtex entry
    Q = 0.23 #eV for copper from schonfelder1997molecular bibtex entry
    GBenergy = 0.708 #J/m^2 from schonfelder1997molecular bibtex entry
  []
[]

[Postprocessors]
  # Scalar postprocessors
  [grain_tracker]
    type = FauxGrainTracker
  []
[]

[Executioner]
  type = Transient
  num_steps = 1
[]

[Outputs]
  exodus = true # Outputs to the Exodus file format
  execute_on = 'final'
[]

[Problem]
  solve = false
[]

(moose/modules/phase_field/test/tests/initial_conditions/TricrystalTripleJunctionIC.i)

# This simulation tests the TricrystalTripleJunctionIC

[Mesh]
  # Mesh block. Meshes can be read in or automatically generated.
  type = GeneratedMesh
  dim = 2 # Problem dimension
  nx = 11 # Number of elements in the x direction
  ny = 11 # Number of elements in the y direction
  xmax = 1001 # Maximum x-coordinate of mesh
  xmin = 0 # Minimum x-coordinate of mesh
  ymax = 1001 # Maximum y-coordinate of mesh
  ymin = 0 # Minimum y-coordinate of mesh
  elem_type = QUAD4 # Type of elements used in the mesh
  uniform_refine = 3
[]

[GlobalParams]
  # Parameters used by several kernels that are defined globally to simplify input file
  op_num = 3 # Number of order parameters used
  var_name_base = gr # base name of grains
  v = 'gr0 gr1 gr2' # Names of the grains
  theta1 = 135 # Angle the first grain makes at the triple junction
  theta2 = 100 # Angle the second grain makes at the triple junction
  length_scale = 1.0e-9 # Length scale in nm
  time_scale = 1.0e-9 # Time scale in ns
[]

[Variables]
  [gr0]
  []
  [gr1]
  []
  [gr2]
  []
[]

[ICs]
  [gr0_IC]
    type = TricrystalTripleJunctionIC
    variable = gr0
    op_index = 1
  []
  [gr1_IC]
    type = TricrystalTripleJunctionIC
    variable = gr1
    op_index = 2
  []
  [gr2_IC]
    type = TricrystalTripleJunctionIC
    variable = gr2
    op_index = 3
  []
[]

[AuxVariables]
  [bnds]
    # Variable used to visualize the grain boundaries in the simulation
    order = FIRST
    family = LAGRANGE
  []
[]

[Kernels]
  # Kernels block where the kernels defining the residual equations are set up
  [PolycrystalKernel]
    # Custom action creating all necessary kernels for grain growth.  All input parameters are up in GlobalParams
  []
[]

[AuxKernels]
  # AuxKernel block, defining the equations used to calculate the auxvars
  [bnds_aux]
    # AuxKernel that calculates the GB term
    type = BndsCalcAux
    variable = bnds
    execute_on = 'initial timestep_end'
  []
[]

[Materials]
  [material]
    # Material properties
    type = GBEvolution
    T = 450 # Constant temperature of the simulation (for mobility calculation)
    wGB = 14 # Width of the diffuse GB
    GBmob0 = 2.5e-6 #m^4(Js) for copper from schonfelder1997molecular bibtex entry
    Q = 0.23 #eV for copper from schonfelder1997molecular bibtex entry
    GBenergy = 0.708 #J/m^2 from schonfelder1997molecular bibtex entry
  []
[]

[Postprocessors]
  # Scalar postprocessors
  [grain_tracker]
    type = FauxGrainTracker
  []
[]

[Executioner]
  type = Transient
  num_steps = 1
[]

[Outputs]
  exodus = true # Outputs to the Exodus file format
  execute_on = 'final'
[]

[Problem]
  solve = false
[]