ExtrinsicStaticTrappingMaterial

Overview

This class implements the trapping material class for the case where additional extrinsic trapping sites have previously been created due to the influence of heavy particle bombardment.

Note the transient class exists for cases where traps conitnue to be created over time. This class aims only to maintain the final state after some period of particle implantation is complete and the precise distribution of new traps is required for subsequent transport calculations.

Note there are a number of complimentary classes for use in cases where extrinsic trap creation is taking place or has taken place:

Basic material properties

As with all trapping material classes this object calculates the Diffusion coefficient and trapping/detrapping reaction rates which are required by Achlys kernels. Eq. (1), Eq. (2), and Eq. (3) show the equations implemented to achieve this.

is the diffusivity of the species through some material in units of . (1)

, in units of , is the reaction rate for the trapping process and is modelled by Eq. (2) where is the lattice constant in and is the number density of solute sites in the material. (2)

, in units of , is the reaction rate for the de-trapping process from the -th trapping site. This is modelled by the Arrhenius type equation as given by Equation Eq. (3) where E is the energy barrier a trapped atom must overcome to leave the site and is referred to as the attempt frequency. (3)

Trap creation

The rate of extrinsic trap creation in Tungsten irradiated with a particle fluence above is given by Bonnin et al. (2015) and Ogorodnikova et al. (2003) as shown in equation Eq. (4). This accounts for 2 trap-creation processes each parameterised by a creation rate, , and a maximum trap density, .

(4)

This is implemented in the Extrinsic Trapping Material classes according to Eq. (5)

(5)

Where the factor, , in Eq. (5) is given by the expression in Eq. (6)

(6)

Table 1: Symbol meanings

Parameter NameSymbol(s)Unit
Trap Concentration
Flux
Flux reflection fraction
Flux distribution function
Trap creation rate
Plastic deformation depth
Plastic deformation function

Example Input File Syntax

[Variables]
  [./Mobile]
    initial_condition = 0.0
  [../]
  [./Trapped_1]
    initial_condition = 0.0
  [../]
  [./Trapped_2]
    initial_condition = 0.0
  []
  [./Trapped_3]
    initial_condition = 0.0
  []
[]

[Materials]
  [./implant]
    type = ExtrinsicStaticTrappingMaterial
    # Energies
    E_diff = 0.39
    E1 = 0.87
    E2 = 1.0
    E3 = 1.5
    k_boltz = 8.617333E-5
    # pre-exponential rate constants
    v0 = 1.0E13
    D0 = 4.1E-7
    lambda = 1.1E-10
    # unused
    rho = 1 # unecessary scaling factor, do not use
    # site densities
    n_sol = 6
    n1 = 1E-3 #1.0E25
    n2 = 4e-4
    n3a_max = 1e-1
    n3b_max = 1e-2
    # trap creation rates
    eta_a = 6e-4
    eta_b = 2e-4
    trap_evolution_time = 400
    # flux distribution parameters
    flux = 4e-10
    function = Gaussian_implant
    xp = 1e-6
    #Temperature
    const_T = 300
    block = 'Tungsten' #'Implantation_region'
    # thermal properties
    conductivity = 150 # W/K
    Cp = 137 # J/(kg K)
    density = 19300 # kg/m3
  [../]
[]

[Functions]
  [./Gaussian_implant]
    type = ParsedFunction
    value = 'scale * exp( -0.5 * ((x - mean) / sd)^2)'
    vars = 'scale mean sd'
    vals = '0.93e8 4.5e-9 4.5e-9'
  [../]
[]
(problems/thermal_desorption/ogorodnikova/tds_multiapp/resting_multi.i)

Input Parameters

  • CpSpecific heat in J/kg/K

    C++ Type:double

    Options:

    Description:Specific heat in J/kg/K

  • D0The diffusion pre-exponential factor

    C++ Type:double

    Options:

    Description:The diffusion pre-exponential factor

  • E1Trap detrapping energy in eV

    C++ Type:double

    Options:

    Description:Trap detrapping energy in eV

  • E2Trap detrapping energy in eV

    C++ Type:double

    Options:

    Description:Trap detrapping energy in eV

  • E3Trap detrapping energy in eV

    C++ Type:double

    Options:

    Description:Trap detrapping energy in eV

  • E_diffdiffusion energy in eV

    C++ Type:double

    Options:

    Description:diffusion energy in eV

  • conductivityThermal conductivity in W/K

    C++ Type:double

    Options:

    Description:Thermal conductivity in W/K

  • const_Tplaceholder for temperature

    C++ Type:double

    Options:

    Description:placeholder for temperature

  • densityMaterial density in kg/m3

    C++ Type:double

    Options:

    Description:Material density in kg/m3

  • eta_aTrap creation rate - "a" type

    C++ Type:double

    Options:

    Description:Trap creation rate - "a" type

  • eta_bTrap creation rate - "b" type

    C++ Type:double

    Options:

    Description:Trap creation rate - "b" type

  • fluxScaled implantation flux

    C++ Type:double

    Options:

    Description:Scaled implantation flux

  • k_boltzBoltzman constant

    C++ Type:double

    Options:

    Description:Boltzman constant

  • lambdaLattice constant in m-1

    C++ Type:double

    Options:

    Description:Lattice constant in m-1

  • n1possible trapping sites

    C++ Type:double

    Options:

    Description:possible trapping sites

  • n2possible trapping sites

    C++ Type:double

    Options:

    Description:possible trapping sites

  • n3a_maxMaximum trap density - "a" type

    C++ Type:double

    Options:

    Description:Maximum trap density - "a" type

  • n3b_maxMaximum attainted trap density - "b" type

    C++ Type:double

    Options:

    Description:Maximum attainted trap density - "b" type

  • n_soldensity of interstitial sites

    C++ Type:double

    Options:

    Description:density of interstitial sites

  • rhomaterial density in m^-3

    C++ Type:double

    Options:

    Description:material density in m^-3

  • trap_evolution_timePrevious flux exposure time for trap distribution calculation

    C++ Type:double

    Options:

    Description:Previous flux exposure time for trap distribution calculation

  • v0pre-exponential detrapping factor in Arrhenious eq.

    C++ Type:double

    Options:

    Description:pre-exponential detrapping factor in Arrhenious eq.

  • xpregion where trap3 exists

    C++ Type:double

    Options:

    Description:region where trap3 exists

Required Parameters

  • blockThe list of blocks (ids or names) that this object will be applied

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

    Options:

    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 boundary condition applies

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

    Options:

    Description:The list of boundaries (ids or names) 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 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

    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

    Options:

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

  • function0The function describing the implantation flux distribution

    Default:0

    C++ Type:FunctionName

    Options:

    Description:The function describing the implantation flux distribution

  • 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

    Options:

    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.

Optional Parameters

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

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

    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<std::string>

    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<OutputName>

    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

References

  1. X. Bonnin, E. Hodille, N. Ning, C. Sang, and Ch. Grisolia. Rate equations modeling for hydrogen inventory studies during a real tokamak material thermal cycle. Journal of Nuclear Materials, 463:970–973, 2015. PLASMA-SURFACE INTERACTIONS 21. URL: https://www.sciencedirect.com/science/article/pii/S0022311514007375, doi:https://doi.org/10.1016/j.jnucmat.2014.10.053.[BibTeX]
  2. O.V Ogorodnikova, J Roth, and M Mayer. Deuterium retention in tungsten in dependence of the surface conditions. Journal of Nuclear Materials, 313-316:469–477, 2003. Plasma-Surface Interactions in Controlled Fusion Devices 15. URL: https://www.sciencedirect.com/science/article/pii/S0022311502013752, doi:https://doi.org/10.1016/S0022-3115(02)01375-2.[BibTeX]