BufferCEGAIrradiationEigenstrain

Irradiation eigenstrain for Buffer

Description

The irradiation eigenstrain of the buffer is given by Miller et al. (2018) and Ho (1993).

The correlation uses fast fluence with neutron energy threshold E>0.18 MeV. The model performs the fast fluence conversion from E>0.10 MeV to E>0.18 MeV using the 'flux_conversion_factor' parameter.

The functional relationship is calculated for all temperatures. Values at temperatures within validity range are interpolated from values at 600, 1032, and 1350C. Values at temperatures outside validity range are extrapolated from values at 600 and 1032C (below range) or 1032 and 1350C (above range), respectively.

The functional relationship is calculated with density value of 2.25 g/cm for densities exceeding the theoretical density, but results should be considered invalid. Values at densities below 1.0 g/cm are extrapolated from values at 1.2 and 1.0 g/cm. Values at densities above 2.0 g/cm are extrapolated from values at 1.96 and 2.0 g/cm.

A constant irradiation eigenstrain rate is used for fluences (E>0.18 MeV) greater than 3.96x10 n/m.

Isotropic Strain

Here (%) is the isotropic eigenstrain of the buffer, (10 n/m, E>0.18 MeV) is the fast neutron fluence, and through are temperature-dependent polynomial coefficients given in Table 1.

Table 1: Polynomial coefficients at density of 1.96 g/cm.

Temp (C)a1a2a3a4
1350-1.42840-0.195630.18991-0.02591
1032-1.523900.130480.06299-0.01072
600-1.240800.001750.08533-0.01253

The polynomial coefficients at other temperatures are interpolated/extrapolated from Table 1.

The strain is calculated at the temperature of the buffer and adjusted for density by applying an isotropic scaling factor .

The isotropic scaling factor is equal to the ratio of the isotropic strain at a given density to the isotropic strain at a density of 1.96 g/cm.

Here (g/cm) is the density of the buffer.

The isotropic density scaling factor is calculated using the values in Table 2 which shows the relationship between the isotropic strain and density at an irradiation temperature of 1100C and a fast fluence of 3.7x10 n/m (E>0.18 MeV).

Table 2: Isotropic strain at irradiation temperature of 1100C and fast fluence of 3.7x10 n/m (E>0.18 MeV).

          
(g/cm)1.01.21.41.51.61.81.91.962.0
(%)-16.15-13.11-9.98-8.93-6.97-4.42-3.41-2.75-2.33

More details can be found in Ho (1993).

Example Input Syntax

[Materials<<<{"href": "../../../syntax/Materials/index.html"}>>>]
  [irradiation_eigenstrain]
    type = BufferCEGAIrradiationEigenstrain<<<{"description": "Irradiation eigenstrain for Buffer", "href": "BufferCEGAIrradiationEigenstrain.html"}>>>
    eigenstrain_name<<<{"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."}>>> = buffer_irradiation_eigenstrain
    temperature<<<{"description": "Coupled temperature"}>>> = temp
  []
[]
(test/tests/triso/buffer_irradiation_eigenstrain/buffer_irradiation_eigenstrain.i)

Input Parameters

  • 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

    Controllable:No

    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.

  • flux_conversion_factorConvert fast neutron flux E>0.10 to E>0.18 MeV

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Convert fast neutron flux E>0.10 to E>0.18 MeV

  • 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.

  • fast_neutron_fluencefast_neutron_fluenceCoupled fast (E>0.10 MeV) neutron fluence

    Default:fast_neutron_fluence

    C++ Type:MaterialPropertyName

    Unit:(no unit assumed)

    Controllable:No

    Description:Coupled fast (E>0.10 MeV) neutron fluence

  • irradiation_eigenstrain_scale_factor1Scale factor for Buffer irradiation eigenstrain

    Default:1

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Scale factor for Buffer irradiation eigenstrain

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

  • 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. F. Ho. NP-MHTGR: Material Models of Pyrocarbon and Pyrolytic Silicon Carbide. Report CEGA-002820 Rev. 1, CEGA Corporation, July 1993.[BibTeX]
  2. G.K. Miller, D.A. Petti, J.T. Maki, D.L. Knudson, and W.F. Skerjanc. PARFUME Theory and Model Basis Report. Report INL/EXT-08-14497 (Rev.1), Idaho National Laboratory, September 2018.[BibTeX]