ComputeDilatationThermalExpansionFunctionEigenstrain

Computes eigenstrain due to thermal expansion using a function that describes the total dilatation as a function of temperature

Description

This model computes the eigenstrain tensor resulting from isotropic thermal expansion where the temperature-dependent thermal expansion is defined by a user-supplied function that describes the total dilatation as a function of temperature, $var element = document.getElementById("moose-equation-fa8a54d4-b54d-4628-895d-b32a7cad7b35");katex.render("T", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ .

The thermal strain is given by, $(1)var element = document.getElementById("moose-equation-0c3dd0fa-6524-4fbf-ae83-72618a2cc365");katex.render(" \\boldsymbol{\\epsilon}^{th} = \\lambda (T) - \\lambda(T_0) \\boldsymbol{I} ", element, {displayMode:true,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ where $var element = document.getElementById("moose-equation-f4c597c6-6b5f-4b4c-bac7-84534001e926");katex.render("T_0", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the stress free temperature, $var element = document.getElementById("moose-equation-41d32693-5d45-4f69-a21c-7ae331eed786");katex.render("\\lambda", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the function that describes dilatation as a function of temperature, and $var element = document.getElementById("moose-equation-703c1a27-8837-4457-bac8-fceadcc4060d");katex.render("\\boldsymbol{I}", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ is the identity matrix. For this material model, $var element = document.getElementById("moose-equation-a53cfec7-bba4-46e3-bb12-46e35c888b8b");katex.render("\\lambda", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ must be provided as a function.

warning

Functions are not able to handle dual numbers at this time, so no automatic differentiation information can be retained via the $var element = document.getElementById("moose-equation-6d25ab7d-1755-491c-a05c-1ede1719b153");katex.render("\\lambda", element, {displayMode:false,throwOnError:false,macros:{"\\pf":"\\frac{\\partial #1}{\\partial #2}"}});$ function

Example Input File Syntax

[./thermal_expansion_strain]
  type = ComputeDilatationThermalExpansionFunctionEigenstrain
  dilatation_function = cte_dilatation
  stress_free_temperature = 1.5
  temperature = temp
  eigenstrain_name = eigenstrain
[../]

/opt/civet/build_0/moose/modules/tensor_mechanics/test/tests/thermal_expansion_function/dilatation.i

# This test checks the thermal expansion calculated via an dilatation function.
# The coefficient is selected so as to result in a 1e-4 strain in the x-axis, and to cross over
# from positive to negative strain.

[Mesh]
  [./gen]
    type = GeneratedMeshGenerator
    dim = 3
  [../]
[]

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

[AuxVariables]
  [./temp]
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = SMALL
    add_variables = true
    eigenstrain_names = eigenstrain
    generate_output = 'strain_xx strain_yy strain_zz'
  [../]
[]

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

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

  [./back]
    type = DirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
[]

[AuxKernels]
  [./temp]
    type = FunctionAux
    variable = temp
    function = '1 + t'
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 1
    poissons_ratio = 0.3
  [../]
  [./stress]
    type = ComputeLinearElasticStress
  [../]
  [./thermal_expansion_strain]
    type = ComputeDilatationThermalExpansionFunctionEigenstrain
    dilatation_function = cte_dilatation
    stress_free_temperature = 1.5
    temperature = temp
    eigenstrain_name = eigenstrain
  [../]
[]

[Functions]
  [./cte_dilatation]
    type = PiecewiseLinear
    x = '1 2'
    y = '-1e-4 1e-4'
  [../]
[]

[Postprocessors]
  [./disp_x_max]
    type = SideAverageValue
    variable = disp_x
    boundary = right
  [../]
  [./temp_avg]
    type = ElementAverageValue
    variable = temp
  [../]
[]

[Executioner]
  type = Transient

  end_time = 1.0
  dt = 0.1
[]

[Outputs]
  csv = true
[]

The eigenstrain_name parameter value must also be set for the strain calculator, and an example parameter setting is shown below:

[Modules/TensorMechanics/Master]
  [./all]
    strain = SMALL
    add_variables = true
    eigenstrain_names = eigenstrain
    generate_output = 'strain_xx strain_yy strain_zz'
  [../]
[]

/opt/civet/build_0/moose/modules/tensor_mechanics/test/tests/thermal_expansion_function/dilatation.i

# This test checks the thermal expansion calculated via an dilatation function.
# The coefficient is selected so as to result in a 1e-4 strain in the x-axis, and to cross over
# from positive to negative strain.

[Mesh]
  [./gen]
    type = GeneratedMeshGenerator
    dim = 3
  [../]
[]

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

[AuxVariables]
  [./temp]
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = SMALL
    add_variables = true
    eigenstrain_names = eigenstrain
    generate_output = 'strain_xx strain_yy strain_zz'
  [../]
[]

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

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

  [./back]
    type = DirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
[]

[AuxKernels]
  [./temp]
    type = FunctionAux
    variable = temp
    function = '1 + t'
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 1
    poissons_ratio = 0.3
  [../]
  [./stress]
    type = ComputeLinearElasticStress
  [../]
  [./thermal_expansion_strain]
    type = ComputeDilatationThermalExpansionFunctionEigenstrain
    dilatation_function = cte_dilatation
    stress_free_temperature = 1.5
    temperature = temp
    eigenstrain_name = eigenstrain
  [../]
[]

[Functions]
  [./cte_dilatation]
    type = PiecewiseLinear
    x = '1 2'
    y = '-1e-4 1e-4'
  [../]
[]

[Postprocessors]
  [./disp_x_max]
    type = SideAverageValue
    variable = disp_x
    boundary = right
  [../]
  [./temp_avg]
    type = ElementAverageValue
    variable = temp
  [../]
[]

[Executioner]
  type = Transient

  end_time = 1.0
  dt = 0.1
[]

[Outputs]
  csv = true
[]

Input Parameters

dilatation_functionFunction describing the thermal dilatation as a function of temperature
C++ Type:FunctionName
Options:
Description:Function describing the thermal dilatation as a function of temperature
eigenstrain_nameMaterial property name for the eigenstrain tensor computed by this model. IMPORTANT: The name of this property must also be provided to the strain calculator.
C++ Type:std::string
Options:
Description:Material property name for the eigenstrain tensor computed by this model. IMPORTANT: The name of this property must also be provided to the strain calculator.
stress_free_temperatureReference temperature at which there is no thermal expansion for thermal eigenstrain calculation
C++ Type:std::vector
Options:
Description:Reference temperature at which there is no thermal expansion for thermal eigenstrain calculation

Required Parameters

base_nameOptional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases
C++ Type:std::string
Options:
Description:Optional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases
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
computeTrueWhen false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the MaterialBase via MaterialBasePropertyInterface::getMaterialBase(). Non-computed MaterialBases are not sorted for dependencies.
Default:True
C++ Type:bool
Options:
Description:When false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the MaterialBase via MaterialBasePropertyInterface::getMaterialBase(). Non-computed MaterialBases are not sorted for dependencies.
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
temperatureCoupled temperature
C++ Type:std::vector
Options:
Description:Coupled temperature

Optional Parameters

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.
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

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/tensor_mechanics/test/tests/thermal_expansion_function/dilatation.i

modules/tensor_mechanics/test/tests/thermal_expansion_function/dilatation.i

# This test checks the thermal expansion calculated via an dilatation function.
# The coefficient is selected so as to result in a 1e-4 strain in the x-axis, and to cross over
# from positive to negative strain.

[Mesh]
  [./gen]
    type = GeneratedMeshGenerator
    dim = 3
  [../]
[]

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

[AuxVariables]
  [./temp]
  [../]
[]

[Modules/TensorMechanics/Master]
  [./all]
    strain = SMALL
    add_variables = true
    eigenstrain_names = eigenstrain
    generate_output = 'strain_xx strain_yy strain_zz'
  [../]
[]

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

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

  [./back]
    type = DirichletBC
    variable = disp_z
    boundary = back
    value = 0.0
  [../]
[]

[AuxKernels]
  [./temp]
    type = FunctionAux
    variable = temp
    function = '1 + t'
  [../]
[]

[Materials]
  [./elasticity_tensor]
    type = ComputeIsotropicElasticityTensor
    youngs_modulus = 1
    poissons_ratio = 0.3
  [../]
  [./stress]
    type = ComputeLinearElasticStress
  [../]
  [./thermal_expansion_strain]
    type = ComputeDilatationThermalExpansionFunctionEigenstrain
    dilatation_function = cte_dilatation
    stress_free_temperature = 1.5
    temperature = temp
    eigenstrain_name = eigenstrain
  [../]
[]

[Functions]
  [./cte_dilatation]
    type = PiecewiseLinear
    x = '1 2'
    y = '-1e-4 1e-4'
  [../]
[]

[Postprocessors]
  [./disp_x_max]
    type = SideAverageValue
    variable = disp_x
    boundary = right
  [../]
  [./temp_avg]
    type = ElementAverageValue
    variable = temp
  [../]
[]

[Executioner]
  type = Transient

  end_time = 1.0
  dt = 0.1
[]

[Outputs]
  csv = true
[]

Description
Example Input File Syntax
Input Parameters
Input Files

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