PhaseMechanicsTest

DeGeus mechanics test material.

Creates a binary phase indicator tensor used in DeGeus-style mechanics tests. The tensor is initialized to zero everywhere, and a rectangular sub-region is set to 1.0 to represent the second phase. The selected sub-region depends on problem dimension:

3D: a block at the high end in x and z, and the low end in y (size s = 9).
2D: a block at the high end in x and the low end in y (size s = 30).

Example Input File Syntax

Below, PhaseMechanicsTest seeds the phase field; elastic moduli are then mixed from the phase.

[TensorComputes]
  [Initialize]
    [phase]
      type = PhaseMechanicsTest
      buffer = phase
    []
    [K]
      type = ParsedCompute
      buffer = K
      expression = '(1-phase)*Ka + phase*Kb'
      inputs = phase
      constant_names = 'Ka Kb'
      constant_expressions = '0.833 8.33'
    []
    [mu]
      type = ParsedCompute
      buffer = mu
      expression = '(1-phase)*mua + phase*mub'
      inputs = phase
      constant_names = 'mua mub'
      constant_expressions = '0.386 3.86'
    []
  []
[]
!listing-end

Input Parameters

bufferThe buffer this compute is writing to
C++ Type:std::string
Controllable:No
Description:The buffer this compute is writing to

Required Parameters

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:No
Description:Set the enabled status of the MooseObject.

Advanced Parameters

Input Files

(examples/degeus_mechanics/mech.i)

(examples/degeus_mechanics/mech.i)

[Domain]
  dim = 3
  nx = 32
  ny = 32
  nz = 32
  xmax = ${fparse 2*pi}
  ymax = ${fparse 2*pi}
  zmax = ${fparse 2*pi}
  mesh_mode = DUMMY
[]

[TensorComputes]
  [Initialize]
    [Finit]
      type = RankTwoIdentity
      buffer = F
    []

    [phase]
      type = PhaseMechanicsTest
      buffer = phase
    []
    [K]
      type = ParsedCompute
      buffer = K
      expression = '(1-phase)*Ka + phase*Kb'
      inputs = phase
      constant_names = 'Ka Kb'
      constant_expressions = '0.833 8.33'
    []
    [mu]
      type = ParsedCompute
      buffer = mu
      expression = '(1-phase)*mua + phase*mub'
      inputs = phase
      constant_names = 'mua mub'
      constant_expressions = '0.386 3.86'
    []
  []

  [Solve]
    [hyper_elasticity]
      type = HyperElasticIsotropic
      buffer = stress
      F = Fnew
      K = K
      mu = mu
    []

    [root]
      [applied_strain]
        type = MacroscopicShearTensor
        buffer = applied_strain
      []
      [mech]
        type = FFTMechanics
        buffer = Fnew
        F = F
        K = K
        mu = mu
        l_tol = 1e-2
        nl_rel_tol = 2e-2
        nl_abs_tol = 2e-2
        constitutive_model = hyper_elasticity
        stress = stress
        applied_macroscopic_strain = applied_strain
      []
    []
  []

  [Postprocess]
    [displacements]
      type = ComputeDisplacements
      buffer = disp
      F = F
    []
    [vonmises]
      type = ComputeVonMisesStress
      buffer = sV
    []
  []
[]

[TensorSolver]
  # no variables are integrated by this solver (FFTMechanics performs a steady state mechanics solve)
  type = ForwardEulerSolver
  root_compute = root
  # deformation tensor is just forwarded Fnew -> F
  forward_buffer = F
  forward_buffer_new = Fnew
  substeps = 10
[]

[TensorOutputs]
  [deformation_tensor]
    type = XDMFTensorOutput
    buffer = 'disp sV F'
    output_mode = 'OVERSIZED_NODAL CELL CELL'
    enable_hdf5 = true
  []
[]

[Executioner]
  type = Transient
  num_steps = 100
  dt = 0.01
[]

Example Input File Syntax
Input Parameters
Input Files