ADPowerLawCreepStressUpdate

This class uses the stress update material in a radial return isotropic power law creep model. This class can be used in conjunction with other creep and plasticity materials for more complex simulations.

Description

In this numerical approach, a trial stress is calculated at the start of each simulation time increment; the trial stress calculation assumed all of the new strain increment is elastic strain:

$var element = document.getElementById("moose-equation-461ada3b-19d9-4c29-926a-819ce3db1819");katex.render("\\sigma_{trial} = C_{ijkl} \\left( \\Delta \\epsilon_{assumed-elastic} + \\epsilon_{elastic}^{old} \\right)", element, {displayMode:true,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$

The algorithms checks to see if the trial stress state is outside of the yield surface, as shown in the figure to the right. If the stress state is outside of the yield surface, the algorithm recomputes the scalar effective inelastic strain required to return the stress state to the yield surface. This approach is given the name Radial Return because the yield surface used is the von Mises yield surface: in the devitoric stress space, this yield surface has the shape of a circle, and the scalar inelastic strain is assumed to always be directed at the circle center.

Recompute Iterations on the Effective Plastic Strain Increment

The recompute radial return materials each individually calculate, using the Newton Method, the amount of effective inelastic strain required to return the stress state to the yield surface.

$var element = document.getElementById("moose-equation-ec837c12-a333-4a5d-82e9-9ea915f345fc");katex.render("\\Delta p^{(t+1)} = \\Delta p^t + d \\Delta p", element, {displayMode:true,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$

where the change in the iterative effective inelastic strain is defined as the yield surface over the derivative of the yield surface with respect to the inelastic strain increment.

The increment of inelastic strain is computed from the creep rate in this class.

$(1)var element = document.getElementById("moose-equation-db3efb56-838d-403b-9fb3-6fb40844a947");katex.render(" \\dot{\\epsilon} = \\left( \\sigma^{trial}_{effective} - 3 G \\Delta p \\right)^n exp \\left( \\frac{-Q}{RT} \\right) \\left(t - t_o \\right)^m", element, {displayMode:true,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$

where $var element = document.getElementById("moose-equation-560ce96b-3a44-4e83-b0c5-411a437e116b");katex.render("\\sigma^{trial}_{effective}", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the scalar von Mises trial stress, $var element = document.getElementById("moose-equation-269af242-c54e-4fc0-acb1-09aa592b16d8");katex.render("G", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the isotropic shear modulus, $var element = document.getElementById("moose-equation-111aa147-75af-4be9-ae8e-5aca21e843f4");katex.render("Q", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the activation energy, $var element = document.getElementById("moose-equation-f1566cb3-7ea1-4834-b700-299e73113af7");katex.render("R", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the universal gas constant, $var element = document.getElementById("moose-equation-e59643d3-5615-443a-808b-c39e4dbe9b16");katex.render("T", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the temperature, $var element = document.getElementById("moose-equation-3ebf1d3a-7453-44ba-82ed-847b4469cd7a");katex.render("t", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ and $var element = document.getElementById("moose-equation-cbb99e52-dc31-44f0-bc36-f002da1f0937");katex.render("t_o", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ are the current and initial times, respectively, and $var element = document.getElementById("moose-equation-c7977fc0-b324-416e-829e-756a0f511d52");katex.render("n", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ and $var element = document.getElementById("moose-equation-5649e500-97f7-4b8c-a1d6-aa4b64349d80");katex.render("m", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ are exponent values.

This class calculates an effective trial stress, an effective creep strain rate increment and the derivative of the creep strain rate, and an effective scalar inelastic strain increment; these values are passed to the ADRadialReturnStressUpdate to compute the radial return stress increment. This isotropic plasticity class also computes the plastic strain as a stateful material property.

This class is based on the implicit integration algorithm in Dunne and Petrinic (2005) pg. 146 - 149.

ADPowerLawCreepStressUpdate must be run in conjunction with an inelastic strain return mapping stress calculator such as ADComputeMultipleInelasticStress

Input Parameters

activation_energyActivation energy
C++ Type:double
Options:
Description:Activation energy
coefficientLeading coefficient in power-law equation
C++ Type:double
Options:
Description:Leading coefficient in power-law equation
n_exponentExponent on effective stress in power-law equation
C++ Type:double
Options:
Description:Exponent on effective stress in power-law equation

Required Parameters

absolute_tolerance1e-11Absolute convergence tolerance for Newton iteration
Default:1e-11
C++ Type:double
Options:
Description:Absolute convergence tolerance for Newton iteration
acceptable_multiplier10Factor applied to relative and absolute tolerance for acceptable convergence if iterations are no longer making progress
Default:10
C++ Type:double
Options:
Description:Factor applied to relative and absolute tolerance for acceptable convergence if iterations are no longer making progress
base_nameOptional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.
C++ Type:std::string
Options:
Description:Optional parameter that defines a prefix for all material properties related to this stress update model. This allows for multiple models of the same type to be used without naming conflicts.
blockThe list of block ids (SubdomainID) that this object will be applied
C++ Type:std::vector
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
Options:
Description:The list of boundary IDs from the mesh where this boundary condition applies
constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped
Default:NONE
C++ Type:MooseEnum
Options:NONE ELEMENT SUBDOMAIN
Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped
gas_constant8.3143Universal gas constant
Default:8.3143
C++ Type:double
Options:
Description:Universal gas constant
m_exponent0Exponent on time in power-law equation
Default:0
C++ Type:double
Options:
Description:Exponent on time in power-law equation
max_inelastic_increment0.0001The maximum inelastic strain increment allowed in a time step
Default:0.0001
C++ Type:double
Options:
Description:The maximum inelastic strain increment allowed in a time step
relative_tolerance1e-08Relative convergence tolerance for Newton iteration
Default:1e-08
C++ Type:double
Options:
Description:Relative convergence tolerance for Newton iteration
start_time0Start time (if not zero)
Default:0
C++ Type:double
Options:
Description:Start time (if not zero)
temperatureCoupled temperature
C++ Type:std::vector
Options:
Description:Coupled temperature

Optional Parameters

apply_strainTrueFlag to apply strain. Used for testing.
Default:True
C++ Type:bool
Options:
Description:Flag to apply strain. Used for testing.
control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector
Options:
Description:Adds user-defined labels for accessing object parameters via control logic.
effective_inelastic_strain_nameeffective_creep_strainName of the material property that stores the effective inelastic strain
Default:effective_creep_strain
C++ Type:std::string
Options:
Description:Name of the material property that stores the effective inelastic strain
enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Options:
Description:Set the enabled status of the MooseObject.
implicitTrueDetermines whether this object is calculated using an implicit or explicit form
Default:True
C++ Type:bool
Options:
Description:Determines whether this object is calculated using an implicit or explicit form
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

internal_solve_full_iteration_historyFalseSet true to output full internal Newton iteration history at times determined by `internal_solve_output_on`. If false, only a summary is output.
Default:False
C++ Type:bool
Options:
Description:Set true to output full internal Newton iteration history at times determined by `internal_solve_output_on`. If false, only a summary is output.
internal_solve_output_onon_errorWhen to output internal Newton solve information
Default:on_error
C++ Type:MooseEnum
Options:never on_error always
Description:When to output internal Newton solve information

Debug Parameters

output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)
C++ Type:std::vector
Options:
Description:List of material properties, from this material, to output (outputs must also be defined to an output type)
outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object
Default:none
C++ Type:std::vector
Options:
Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object

Outputs Parameters

Input Files

modules/combined/test/tests/ad_power_law_creep/power_law_creep_smallstrain.i
modules/combined/test/tests/ad_power_law_creep/power_law_creep_restart2.i
modules/combined/test/tests/ad_power_law_creep/power_law_creep_simple.i
modules/tensor_mechanics/test/tests/ad_viscoplasticity_stress_update/creep.i
modules/tensor_mechanics/test/tests/ad_plastic/power_law_creep.i
modules/combined/test/tests/ad_power_law_creep/power_law_creep.i
modules/combined/test/tests/ad_power_law_creep/power_law_creep_restart1.i

modules/combined/test/tests/ad_power_law_creep/power_law_creep_smallstrain.i

# 1x1x1 unit cube with uniform pressure on top face for the case of small strain.
#  This test does not have a solid mechanics analog because there is not an equvialent
#  small strain with rotations strain calculator material in solid mechanics

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  type = GeneratedMesh
  dim = 3
  nx = 1
  ny = 1
  nz = 1
[]

[Variables]
  [./temp]
    order = FIRST
    family = LAGRANGE
    initial_condition = 1000.0
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = SMALL
    incremental = true
    add_variables = true
    generate_output = 'stress_yy creep_strain_xx creep_strain_yy creep_strain_zz elastic_strain_yy'
    use_automatic_differentiation = true
  [../]
[]

[Functions]
  [./top_pull]
    type = PiecewiseLinear
    x = '0 1'
    y = '1 1'
  [../]
[]

[Kernels]
  [./heat]
    type = ADHeatConduction
    variable = temp
  [../]
  [./heat_ie]
    type = ADHeatConductionTimeDerivative
    variable = temp
  [../]
[]

[BCs]
  [./u_top_pull]
    type = ADPressure
    variable = disp_y
    component = 1
    boundary = top
    constant = -10.0e6
    function = top_pull
  [../]
  [./u_bottom_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./u_yz_fix]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./u_xy_fix]
    type = ADDirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
  [./temp_fix]
    type = DirichletBC
    variable = temp
    boundary = 'bottom top'
    value = 1000.0
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 2e11
    poissons_ratio = 0.3
  [../]
  [./radial_return_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = 'power_law_creep'
  [../]
  [./power_law_creep]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1.0e-15
    n_exponent = 4
    activation_energy = 3.0e5
    temperature = temp
  [../]

  [./thermal]
    type = HeatConductionMaterial
    specific_heat = 1.0
    thermal_conductivity = 100.
  [../]
  [./density]
    type = ADDensity
    density = 1.0
  [../]
[]

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

[Executioner]
  type = Transient

  solve_type = 'PJFNK'

  petsc_options = '-snes_ksp_ew'
  petsc_options_iname = '-ksp_gmres_restart'
  petsc_options_value = '101'

  line_search = 'none'

  l_max_its = 20
  nl_max_its = 20
  nl_rel_tol = 1e-6
  nl_abs_tol = 1e-6
  l_tol = 1e-5
  start_time = 0.0
  end_time = 1.0
  num_steps = 10
  dt = 0.1
[]

[Outputs]
  exodus = true
[]

modules/combined/test/tests/ad_power_law_creep/power_law_creep_restart2.i

# 1x1x1 unit cube with uniform pressure on top face

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  type = GeneratedMesh
  dim = 3
  nx = 1
  ny = 1
  nz = 1
[]

[Variables]
  [./temp]
    order = FIRST
    family = LAGRANGE
    initial_condition = 1000.0
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = FINITE
    incremental = true
    add_variables = true
    generate_output = 'stress_yy creep_strain_xx creep_strain_yy creep_strain_zz elastic_strain_yy'
    use_automatic_differentiation = true
  [../]
[]

[Functions]
  [./top_pull]
    type = PiecewiseLinear
    x = '0 1'
    y = '1 1'
  [../]
[]

[Kernels]
  [./heat]
    type = ADHeatConduction
    variable = temp
  [../]
  [./heat_ie]
    type = ADHeatConductionTimeDerivative
    variable = temp
  [../]
[]

[BCs]
  [./u_top_pull]
    type = ADPressure
    variable = disp_y
    component = 1
    boundary = top
    constant = -10.0e6
    function = top_pull
  [../]
  [./u_bottom_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./u_yz_fix]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./u_xy_fix]
    type = ADDirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
  [./temp_fix]
    type = DirichletBC
    variable = temp
    boundary = 'bottom top'
    value = 1000.0
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 2e11
    poissons_ratio = 0.3
  [../]
  [./radial_return_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = 'power_law_creep'
  [../]
  [./power_law_creep]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1.0e-15
    n_exponent = 4
    activation_energy = 3.0e5
    temperature = temp
  [../]

  [./thermal]
    type = HeatConductionMaterial
    specific_heat = 1.0
    thermal_conductivity = 100.
  [../]
  [./density]
    type = ADDensity
    density = 1.0
  [../]
[]

[Executioner]
  type = Transient

  solve_type = 'PJFNK'

  petsc_options = '-snes_ksp'
  petsc_options_iname = '-ksp_gmres_restart'
  petsc_options_value = '101'

  line_search = 'none'

  l_max_its = 20
  nl_max_its = 20
  nl_rel_tol = 1e-6
  nl_abs_tol = 1e-6
  l_tol = 1e-5
  start_time = 0.6
  end_time = 1.0
  num_steps = 12
  dt = 0.1
[]

[Outputs]
  file_base = power_law_creep_out
  exodus = true
[]

[Problem]
  restart_file_base = power_law_creep_restart1_out_cp/0006
[]

modules/combined/test/tests/ad_power_law_creep/power_law_creep_simple.i

# 1x1x1 unit cube with uniform pressure on top face

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  type = GeneratedMesh
  dim = 3
[]

[AuxVariables]
  [./temp]
    initial_condition = 1000.0
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = FINITE
    incremental = true
    add_variables = true
    generate_output = 'stress_yy creep_strain_xx creep_strain_yy creep_strain_zz elastic_strain_yy'
    use_automatic_differentiation = true
  [../]
[]
[BCs]
  [./u_top_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = top
    value = 1e-5
  [../]
  [./u_bottom_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./u_yz_fix]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./u_xy_fix]
    type = ADDirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 2e11
    poissons_ratio = 0.3
  [../]
  [./radial_return_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = 'power_law_creep'
  [../]
  [./power_law_creep]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1.0e-15
    n_exponent = 4
    activation_energy = 3.0e5
    temperature = temp
  [../]
[]

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

[Executioner]
  type = Transient
  solve_type = 'PJFNK'

  num_steps = 10
  dt = 0.1
[]

[Outputs]
  exodus = true
[]

modules/tensor_mechanics/test/tests/ad_viscoplasticity_stress_update/creep.i

# This test is provided as a check to ensure ADComputeMultiplePorousInelasticStress

[GlobalParams]
  displacements = 'disp_x disp_y'
[]

[Mesh]
  type = GeneratedMesh
  dim = 2
  nx = 2
  ny = 2
  xmax = 0.002
  ymax = 0.002
[]

[Modules/TensorMechanics/Master/All]
  strain = FINITE
  add_variables = true
  base_name = 'total'
  generate_output = 'strain_xx strain_yy strain_xy hydrostatic_stress vonmises_stress'
  use_automatic_differentiation = true
[]

[Functions]
  [./pull]
    type = PiecewiseLinear
    x = '0 0.1'
    y = '0 1e-5'
  [../]
[]

[Materials]
  active='elasticity_tensor porous_stress creep'
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 1e10
    poissons_ratio = 0.3
    base_name = 'total'
  [../]
  [./porous_stress]
    type = ADComputeMultiplePorousInelasticStress
    inelastic_models = creep
    initial_porosity = 0.1
    outputs = all
    base_name = 'total'
  [../]
  [./regular_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = creep
    outputs = all
    base_name = 'total'
  [../]
  [./porosity]
    type = GenericConstantMaterial
    prop_names = porosity
    prop_values = 0.1
    outputs = all
  [../]
  [./creep]
    type = ADPowerLawCreepStressUpdate
    activation_energy = 4e4
    temperature = 1200
    coefficient = 1e-18
    gas_constant = 1.987
    n_exponent = 3
    base_name = 'creep'
    outputs = all
  [../]
[]

[BCs]
  [./no_disp_x]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./no_disp_y]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./pull_disp_y]
    type = ADFunctionDirichletBC
    variable = disp_y
    boundary = top
    function = pull
  [../]
[]

[Executioner]
  type = Transient
  solve_type = NEWTON
  dt = 0.01
  end_time = 0.12
[]

[Postprocessors]
  [./disp_x]
    type = SideAverageValue
    variable = disp_x
    boundary = right
  [../]
  [./disp_y]
    type = SideAverageValue
    variable = disp_y
    boundary = top
  [../]
  [./avg_hydro]
    type = ElementAverageValue
    variable = total_hydrostatic_stress
  [../]
  [./avg_vonmises]
    type = ElementAverageValue
    variable = total_vonmises_stress
  [../]
  [./dt]
    type = TimestepSize
  [../]
  [./num_lin]
    type = NumLinearIterations
    outputs = console
  [../]
  [./num_nonlin]
    type = NumNonlinearIterations
    outputs = console
  [../]
  [./eff_creep_strain]
    type = ElementAverageValue
    variable = creep_effective_creep_strain
  [../]
  [./porosity]
    type = ElementAverageValue
    variable = porosity
  [../]
[]

[Outputs]
  csv = true
[]

modules/tensor_mechanics/test/tests/ad_plastic/power_law_creep.i

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

[GlobalParams]
  displacements = 'disp_x disp_y'
  volumetric_locking_correction = false
[]

[AuxVariables]
  [./hydrostatic_stress]
    order = CONSTANT
    family = MONOMIAL
  [../]
[]

[AuxKernels]
  [./hydrostatic_stress]
    type = RankTwoScalarAux
    variable = hydrostatic_stress
    rank_two_tensor = stress
    scalar_type = Hydrostatic
  [../]
[]

[Variables]
  [./disp_x]
    order = SECOND
    scaling = 1e-10
  [../]
  [./disp_y]
    order = SECOND
    scaling = 1e-10
  [../]
[]

[Functions]
  [./pull]
    type = PiecewiseLinear
    x = '0 10'
    y = '0 1e-3'
  [../]
[]

[Kernels]
  [./stress_x]
    type = ADStressDivergenceTensors
    component = 0
    variable = disp_x
  [../]
  [./stress_y]
    type = ADStressDivergenceTensors
    component = 1
    variable = disp_y
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 1e10
    poissons_ratio = 0.3
  [../]
  [./strain]
    type = ADComputeIncrementalSmallStrain
  [../]
  [./elastic_strain]
    type = ADComputeMultipleInelasticStress
  [../]

  [./creep_ten]
    type = ADPowerLawCreepStressUpdate
    coefficient = 10e-24
    n_exponent = 4
    activation_energy = 0
    base_name = creep_ten
  [../]
  [./creep_ten2]
    type = ADPowerLawCreepStressUpdate
    coefficient = 10e-24
    n_exponent = 4
    activation_energy = 0
    base_name = creep_ten2
  [../]
  [./creep_one]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1e-24
    n_exponent = 4
    activation_energy = 0
    base_name = creep_one
  [../]
  [./creep_nine]
    type = ADPowerLawCreepStressUpdate
    coefficient = 9e-24
    n_exponent = 4
    activation_energy = 0
    base_name = creep_nine
  [../]
  [./creep_zero]
    type = ADPowerLawCreepStressUpdate
    coefficient = 0e-24
    n_exponent = 4
    activation_energy = 0
    base_name = creep_zero
  [../]
[]

[BCs]
  [./no_disp_x]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]

  [./no_disp_y]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]

  [./pull_disp_y]
    type = ADFunctionDirichletBC
    variable = disp_y
    boundary = top
    function = pull
  [../]
[]

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

[Executioner]
  type = Transient

  petsc_options_iname = -pc_hypre_type
  petsc_options_value = boomeramg

  line_search = 'none'
  nl_rel_tol = 1e-5

  num_steps = 5
  dt = 1e-1
[]

[Postprocessors]
  [./max_disp_x]
    type = ElementExtremeValue
    variable = disp_x
  [../]
  [./max_disp_y]
    type = ElementExtremeValue
    variable = disp_y
  [../]
  [./max_hydro]
    type = ElementAverageValue
    variable = hydrostatic_stress
  [../]
  [./dt]
    type = TimestepSize
  [../]
  [./num_lin]
    type = NumLinearIterations
    outputs = console
  [../]
  [./num_nonlin]
    type = NumNonlinearIterations
    outputs = console
  [../]
[]

[Outputs]
  csv = true
[]

modules/combined/test/tests/ad_power_law_creep/power_law_creep.i

# 1x1x1 unit cube with uniform pressure on top face

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  type = GeneratedMesh
  dim = 3
[]

[Variables]
  [./temp]
    initial_condition = 1000.0
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = FINITE
    incremental = true
    add_variables = true
    generate_output = 'stress_yy creep_strain_xx creep_strain_yy creep_strain_zz elastic_strain_yy'
    use_automatic_differentiation = true
  [../]
[]

[Kernels]
  [./heat]
    type = ADHeatConduction
    variable = temp
  [../]
  [./heat_ie]
    type = ADHeatConductionTimeDerivative
    variable = temp
  [../]
[]

[BCs]
  [./u_top_pull]
    type = ADPressure
    variable = disp_y
    component = 1
    boundary = top
    constant = -10.0e6
  [../]
  [./u_bottom_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./u_yz_fix]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./u_xy_fix]
    type = ADDirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
  [./temp_fix]
    type = DirichletBC
    variable = temp
    boundary = 'bottom top'
    value = 1000.0
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 2e11
    poissons_ratio = 0.3
  [../]
  [./radial_return_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = 'power_law_creep'
  [../]
  [./power_law_creep]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1.0e-15
    n_exponent = 4
    activation_energy = 3.0e5
    temperature = temp
  [../]

  [./thermal]
    type = HeatConductionMaterial
    specific_heat = 1.0
    thermal_conductivity = 100.
  [../]
  [./density]
    type = ADDensity
    density = 1.0
  [../]
[]

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

[Executioner]
  type = Transient
  solve_type = 'PJFNK'

  petsc_options = '-snes_ksp'
  petsc_options_iname = '-ksp_gmres_restart'
  petsc_options_value = '101'

  line_search = 'none'

  l_max_its = 20
  nl_max_its = 20
  nl_rel_tol = 1e-6
  nl_abs_tol = 1e-6
  l_tol = 1e-5
  start_time = 0.0
  end_time = 1.0
  num_steps = 10
  dt = 0.1
[]

[Outputs]
  exodus = true
[]

modules/combined/test/tests/ad_power_law_creep/power_law_creep_restart1.i

# 1x1x1 unit cube with uniform pressure on top face

[GlobalParams]
  displacements = 'disp_x disp_y disp_z'
[]

[Mesh]
  type = GeneratedMesh
  dim = 3
  nx = 1
  ny = 1
  nz = 1
[]

[Variables]
  [./temp]
    order = FIRST
    family = LAGRANGE
    initial_condition = 1000.0
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = FINITE
    incremental = true
    add_variables = true
    generate_output = 'stress_yy creep_strain_xx creep_strain_yy creep_strain_zz elastic_strain_yy'
    use_automatic_differentiation = true
  [../]
[]

[Functions]
  [./top_pull]
    type = PiecewiseLinear
    x = '0 1'
    y = '1 1'
  [../]
[]

[Kernels]
  [./heat]
    type = ADHeatConduction
    variable = temp
  [../]
  [./heat_ie]
    type = ADHeatConductionTimeDerivative
    variable = temp
  [../]
[]

[BCs]
  [./u_top_pull]
    type = ADPressure
    variable = disp_y
    component = 1
    boundary = top
    constant = -10.0e6
    function = top_pull
  [../]
  [./u_bottom_fix]
    type = ADDirichletBC
    variable = disp_y
    boundary = bottom
    value = 0.0
  [../]
  [./u_yz_fix]
    type = ADDirichletBC
    variable = disp_x
    boundary = left
    value = 0.0
  [../]
  [./u_xy_fix]
    type = ADDirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
  [./temp_fix]
    type = DirichletBC
    variable = temp
    boundary = 'bottom top'
    value = 1000.0
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 2e11
    poissons_ratio = 0.3
  [../]
  [./radial_return_stress]
    type = ADComputeMultipleInelasticStress
    inelastic_models = 'power_law_creep'
  [../]
  [./power_law_creep]
    type = ADPowerLawCreepStressUpdate
    coefficient = 1.0e-15
    n_exponent = 4
    activation_energy = 3.0e5
    temperature = temp
  [../]

  [./thermal]
    type = HeatConductionMaterial
    specific_heat = 1.0
    thermal_conductivity = 100.
  [../]
  [./density]
    type = ADDensity
    density = 1.0
  [../]
[]

[Executioner]
  type = Transient
  solve_type = 'PJFNK'

  petsc_options = '-snes_ksp'
  petsc_options_iname = '-ksp_gmres_restart'
  petsc_options_value = '101'

  line_search = 'none'

  l_max_its = 20
  nl_max_its = 20
  nl_rel_tol = 1e-6
  nl_abs_tol = 1e-6
  l_tol = 1e-5
  start_time = 0.0
  end_time = 1.0
  num_steps = 6
  dt = 0.1
[]

[Outputs]
  exodus = true
  csv = true
  [./out]
    type = Checkpoint
    num_files = 1
  [../]
[]

Child Objects

modules/combined/test/include/materials/ADPowerLawCreepExceptionTest.h

modules/combined/test/include/materials/ADPowerLawCreepExceptionTest.h

// This file is part of the MOOSE framework
// https://www.mooseframework.org
//
// All rights reserved, see COPYRIGHT for full restrictions
// https://github.com/idaholab/moose/blob/master/COPYRIGHT
//
// Licensed under LGPL 2.1, please see LICENSE for details
// https://www.gnu.org/licenses/lgpl-2.1.html

#pragma once

#include "ADPowerLawCreepStressUpdate.h"

template <ComputeStage compute_stage>
class ADPowerLawCreepExceptionTest;

declareADValidParams(ADPowerLawCreepExceptionTest);

template <ComputeStage compute_stage>
class ADPowerLawCreepExceptionTest : public ADPowerLawCreepStressUpdate<compute_stage>
{
public:
  ADPowerLawCreepExceptionTest<compute_stage>(const InputParameters & parameters);

  static InputParameters validParams();

protected:
  virtual ADReal computeResidual(const ADReal & effective_trial_stress,
                                 const ADReal & scalar) override;
  virtual ADReal computeDerivative(const ADReal & effective_trial_stress,
                                   const ADReal & scalar) override;

  usingRadialReturnCreepStressUpdateBaseMembers;
};

References

Fionn Dunne and Nik Petrinic. Introduction to Computational Plasticity. Oxford University Press on Demand, 2005.

@book{dunne2005introduction,
    author = "Dunne, Fionn and Petrinic, Nik",
    title = "Introduction to Computational Plasticity",
    year = "2005",
    publisher = "Oxford University Press on Demand"
}

Description
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