FCCI Interaction Layer Thickness AuxKernel

Calculates the FCCI layer thickness using the boundary mass flux.

Description

The ThicknessLayerFCCI AuxKernel is used to calculate the interaction layer thickness during Fuel-Clad Chemical Interaction for metal fuels. The mass flux through the boundary is required from a Postprocessor. The change in thickness layer is then applied to the Variable storing the thickness layer on the boundary. The boundary may be an internal boundary. The growth of the interaction layer assumes the same sign as the normal mass flux. Negative thickness values correspond to negative flux values with respect to the boundary normal. If the boundary normal is in the same direction as the mass flux, the thickness layer would be positive as well. The GapHeatTransfer thermal contact model may be used to provide gap species diffusion to calculate mass flux across gap sections.

For metal fuel, the Fuel-Clad Chemical Interaction layer develops as fission products diffuse from the fuel into the cladding. During long transients, such as burnup simulations, an interaction layer develops in the clad. In Bison, the change in thickness layer is tracked similar to the approach used in Karahan and Buongiorno (2010). Two methods are provided to related mass flux at a boundary to interaction layer growth.

The first method is adapted from Carmack (2012) to be a change in layer thickness. The interaction layer thickness was given as (1) where is the mass flux through the boundary, is the interaction layer thickness at time , is the density of the layer, and is the molecular weight of the layer. Eq. 1 may be easily arranged into a change in thickness, , relation assuming the mass flux is constant over the giving (2) assuming the thickness layer growth is the same direction of the mass flux according to the boundary normal.

The second method is provided by Ogata et al. (2003) relating the movement of the boundary between two diffusion couples to the mass flux across the boundary. The relation is given as (3) where is the solubility fraction of the fission product, is the solubility limit of the fission product in the fuel, and the right side terms are the mass flux across the boundary. As the fuel is producing fission products the boundary moves in the opposite direction than in diffusion couples. As long as the solubility fraction remains above the fuel solubility limit, the change in thickness is (4) assuming the thickness layer growth is the same direction of the mass flux according to the boundary normal.

Example Input Syntax


[AuxKernels]
  [./fcci_layer]
    boundary = right
    execute_on = timestep_end
    method = 1
    postproc_flux = right_flux
    type = ThicknessLayerFCCI
    variable = thickness
  [../]
[]
(test/tests/fcci_ht9/fcci_ht9.i)

Input Parameters

  • variableThe name of the variable that this object applies to

    C++ Type:AuxVariableName

    Description:The name of the variable that this object applies to

  • postproc_fluxThe postproccessor which provides the mass flux through the boundary.

    C++ Type:PostprocessorName

    Description:The postproccessor which provides the mass flux through the boundary.

  • methodMethod for calculating the FCCI layer thickness: 1=Delta Carmack, 2=Ogata

    C++ Type:int

    Description:Method for calculating the FCCI layer thickness: 1=Delta Carmack, 2=Ogata

Required Parameters

  • solubility_speciesCoupled species solubility value variable

    C++ Type:std::vector

    Description:Coupled species solubility value variable

  • layer_density7700Interaction layer density

    Default:7700

    C++ Type:double

    Description:Interaction layer density

  • solubility_fuel0Solubility limit of the species in the fuel

    Default:0

    C++ Type:double

    Description:Solubility limit of the species in the fuel

  • layer_mol_weight1.215Interaction Layer molecular weight

    Default:1.215

    C++ Type:double

    Description:Interaction Layer molecular weight

  • execute_onLINEARThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.

    Default:LINEAR

    C++ Type:ExecFlagEnum

    Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.

  • boundaryThe list of boundary IDs from the mesh where this boundary condition applies

    C++ Type:std::vector

    Description:The list of boundary IDs from the mesh where this boundary condition applies

  • blockThe list of block ids (SubdomainID) that this object will be applied

    C++ Type:std::vector

    Description:The list of block ids (SubdomainID) that this object will be applied

  • initial_contact_time0Time at which interaction layer begins forming.

    Default:0

    C++ Type:double

    Description:Time at which interaction layer begins forming.

Optional Parameters

  • control_tagsAdds user-defined labels for accessing object parameters via control logic.

    C++ Type:std::vector

    Description:Adds user-defined labels for accessing object parameters via control logic.

  • enableTrueSet the enabled status of the MooseObject.

    Default:True

    C++ Type:bool

    Description:Set the enabled status of the MooseObject.

  • seed0The seed for the master random number generator

    Default:0

    C++ Type:unsigned int

    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

    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

Input Files

References

  1. W. J. Carmack. Temperature and burnup correlated FCCI in U-10Zr metallic fuel. Technical Report INL/EXT-12-25550, Idaho National Laboratory, May 2012.[BibTeX]
  2. A. Karahan and J. Buongiorno. A new code for predicting the thermo-mechanical and irradiation behavior of metallic fuels in sodium fast reactors. Journal of Nuclear Materials, 396:283–293, 2010.[BibTeX]
  3. T. Ogata, M. Akabori, and A. Itoh. Diffusion of cerium in uranium-zirconium solid solutions. Materials Transactions, 44(1):47–52, 2003.[BibTeX]