UCOElasticityTensor

Computes the Young's modulus (Pa) and elastic Poisson's ratio (dimensionless) for UCO.

Description

Figure 16.4 in Section 16.2 of Olander (1976) was used to fit the temperature dependence of the elastic modulus. Equation 16.1a in Section 16.2 of reference (Olander, 1976) shows the density dependence of the elastic modulus. The elastic modulus at room temperature is assumed to be 219 GPa. Functional relationships derived from experimental data on UO2 and assumed valid for UCO due to lack of relevant UCO data.

Elastic Modulus

where (GPa) is the elastic modulus of the kernel, (C) is the temperature of the kernel, (g/cm) is the density of the kernel, and (g/cm) is the theoretical density of UCO.

Theoretical density of UCO is calculated in TRISOUtils.

Poisson's Ratio

The Poisson's ratio of the kernel, (-) is given by:

where (g/cm) is the density of the kernel and (g/cm) is the theoretical density of UCO.

Validity Range

Temperature: 25 - 1300 C and value at 1300 C is used for temperature above 1300 C.

Density: assumed valid at all densities.

Function Fitting Procedure

Figure 1: Temperature dependence of the Young’s modulus of UO2 (Figure 16.4 in Section 16.2 of Olander (1976)).

The temperature-dependence of the Young’s () modulus of UO2 are given by Figure 2. A plot digitizer was used to digitize the curves. The resulting fits obtained by 4-order polynomial regression in Excel are shown in Figure 2. They are approximated by:

Figure 2: Fitted temperature dependence of the Young’s modulus of UO2.

Example Input Syntax

[Materials<<<{"href": "../../../syntax/Materials/index.html"}>>>]
  [elasticity_tensor]
    type = UCOElasticityTensor<<<{"description": "Computes the Young's modulus (Pa) and elastic Poisson's ratio (dimensionless) for UCO.", "href": "UCOElasticityTensor.html"}>>>
    temperature<<<{"description": "Coupled temperature"}>>> = temperature
  []
[]
(test/tests/triso/UCOElasticityTensor/UCOElasticityTensor.i)

Input Parameters

  • C_UCarbon/Uranium initial stoichiometry

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Carbon/Uranium initial stoichiometry

  • O_UOxygen/Uranium initial stoichiometry

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Oxygen/Uranium initial stoichiometry

  • initial_enrichmentinitial enrichment fraction of U235 (wt%)

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:initial enrichment fraction of U235 (wt%)

  • temperatureCoupled temperature

    C++ Type:std::vector<VariableName>

    Unit:(no unit assumed)

    Controllable:No

    Description:Coupled temperature

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

    Controllable:No

    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 blocks (ids or names) that this object will be applied

    C++ Type:std::vector<SubdomainName>

    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>

    Controllable:No

    Description:The list of boundaries (ids or names) from the mesh where this object 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

    Controllable:No

    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 computeQpProperties() 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

    Controllable:No

    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 computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

  • declare_suffixAn optional suffix parameter that can be appended to any declared 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 declared properties. The suffix will be prepended with a '_' character.

  • elasticity_tensor_prefactorOptional function to use as a scalar prefactor on the elasticity tensor.

    C++ Type:FunctionName

    Unit:(no unit assumed)

    Controllable:No

    Description:Optional function to use as a scalar prefactor on the elasticity tensor.

Optional 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:Yes

    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

    Controllable:No

    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

    Controllable:No

    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

    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

  • output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

    C++ Type:std::vector<std::string>

    Controllable:No

    Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

  • outputsnone Vector of output names where you would like to restrict the output of variables(s) associated with this object

    Default:none

    C++ Type:std::vector<OutputName>

    Controllable:No

    Description:Vector of output names where you would like to restrict the output of variables(s) associated with this object

Outputs Parameters

  • poissons_ratio_scale_factor1Multiplier for UCO Poisson's ratio

    Default:1

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Multiplier for UCO Poisson's ratio

  • youngs_modulus_scale_factor1Multiplier for UCO Young's modulus

    Default:1

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Multiplier for UCO Young's modulus

Advanced: Scaling Factors Parameters

  • 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.

  • 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

    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.

Material Property Retrieval Parameters

Input Files

References

  1. D.R. Olander. Fundamental Aspects of Nuclear Reactor Fuel Elements. Technical Report, Technical Information Center - Energy Research and Development Administration, 1976.[BibTeX]