ADUPuZrFissionGasRelease

Computes fission gas release for UPuZr metallic fuel

Description

UPuZrFissionGasRelease and its associated AD and non-AD objects contain a fission gas release model for uranium plutonium zirconium (UPuZr) fuel based on the current porosity of the fuel. The model is derived from historical Experimental Breeder Reactor II (EBR-II) post-irradiation examinations that showed that the fission gas release fraction (gas released over gas produced) quickly increased to about 80% between 1 to 2 atom percent burnup, and remained nearly constant throughout the remainder of the irradiation (Hofman et al., 1997). The step-like function of fission gas release is related to the interconnection of porosity, , as the porosity increases past a critical porosity , and becomes interconnected. From these observations, an extremely simple fission gas release model can be formulated in the absence of more advanced mechanistic models, (1) where and are the total gas density released and produced at time , respectively, in (mols/m). The porosity value utilized in Eq. (1) can be either the current or previous time step, depending on the value of the input parameter use_current_porosity.

The total fission gas produced is related to the fission rate density by, (2) where is the yield of fission gas atoms per fission, typically taken as (gas atoms/m/s), and is Avogadro's number ( atoms/mol). Here, is Optionally, the value of the fission rate at the current time-step can be utilized instead of the average by setting time_average_fission_rate=false, such that in Eq. (2).

The critical porosity value nominally should occur around 25% porosity, corresponding to 33.3% volumetric swelling. The default value of 24% porosity is set to lie between the default interconnection_initiating_porosity=0.23 and interconnection_terminating_porosity=0.25 values set in UPuZrVolumetricSwellingEigenstrain to capture the concurrent fission gas release and swelling termination.

The initial fraction of fission gas released after the critical porosity value is reached and the fraction of the post-interconnection produced fission gas that is released to the plenum can be set using the following parameters, fractional_fgr_initial and fractional_fgr_post. The default values for these parameters are 0.8 and 1.0, respectively.

Example Input Syntax

[Materials<<<{"href": "../../syntax/Materials/index.html"}>>>]
  [fission_gas_release]
    type = ADUPuZrFissionGasRelease<<<{"description": "Computes fission gas release for UPuZr metallic fuel", "href": "UPuZrFissionGasRelease.html"}>>>
    fission_rate<<<{"description": "Fission rate material property name"}>>> = fission_rate
    porosity<<<{"description": "Porosity material property name"}>>> = porosity
    fractional_yield<<<{"description": "fraction yield of fission gas atoms per fission"}>>> = 0.25
    critical_porosity<<<{"description": "Porosity at which fission gas release initiates. This needs to be between the interconnection_initiating_porosity and interconnection_terminating_porosity in UPuZrVolumetricSwellingEigenstrain"}>>> = 0.20
    time_average_fission_rate<<<{"description": "Flag to average the fission rate with the previous time step instead of only using the current fission rate"}>>> = false
    use_old_porosity<<<{"description": "Flag to use old porosity."}>>> = false
    fractional_fgr_initial<<<{"description": "fraction of fission gas produced that is released once the critical porosity is reached"}>>> = 0.7
    fractional_fgr_post<<<{"description": "fraction of fission gas produced that is released after interconnection"}>>> = 0.9
  []
[]
(test/tests/upuzr_fission_gas_release/ad/test.i)

Input Parameters

  • 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

  • critical_porosity0.24Porosity at which fission gas release initiates. This needs to be between the interconnection_initiating_porosity and interconnection_terminating_porosity in UPuZrVolumetricSwellingEigenstrain

    Default:0.24

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Porosity at which fission gas release initiates. This needs to be between the interconnection_initiating_porosity and interconnection_terminating_porosity in UPuZrVolumetricSwellingEigenstrain

  • 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.

  • fission_ratefission_rateFission rate material property name

    Default:fission_rate

    C++ Type:MaterialPropertyName

    Unit:(no unit assumed)

    Controllable:No

    Description:Fission rate material property name

  • fractional_fgr_initial0.8fraction of fission gas produced that is released once the critical porosity is reached

    Default:0.8

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:fraction of fission gas produced that is released once the critical porosity is reached

  • fractional_fgr_post1fraction of fission gas produced that is released after interconnection

    Default:1

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:fraction of fission gas produced that is released after interconnection

  • fractional_yield0.3017fraction yield of fission gas atoms per fission

    Default:0.3017

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:fraction yield of fission gas atoms per fission

  • porosityporosityPorosity material property name

    Default:porosity

    C++ Type:MaterialPropertyName

    Unit:(no unit assumed)

    Controllable:No

    Description:Porosity material property name

  • time_average_fission_rateTrueFlag to average the fission rate with the previous time step instead of only using the current fission rate

    Default:True

    C++ Type:bool

    Controllable:No

    Description:Flag to average the fission rate with the previous time step instead of only using the current fission rate

  • use_old_porosityFalseFlag to use old porosity.

    Default:False

    C++ Type:bool

    Controllable:No

    Description:Flag to use old porosity.

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. G L Hofman, L C Walters, and T H Bauer. Metallic fast reactor fuels. Progress in Nuclear Energy, 31(1-2):83–110, January 1997.[BibTeX]