ThermalGraphiteProperties

Graphite thermal properties.

Description

This userobject provides thermal properties for graphite as a function of temperature. Because there are many different grades of graphite, this userobject computes properties individually for each grade. Because many grades are encapsulated in this userobject, the applicability ranges of the correlations are unique to each grade.

Many of the graphite grades encapsulated in this userobject are coke-based. Because many coke-based graphite grades show approximately the same specific heat, it is a reasonable approximation to use the same CpC_p correlation from Butland and Maddison (1973) for many different grades Baker (1970).

All units are given in SI, such that the input temperature is Kelvin, and the output units of the thermal conductivity kk are W/m\cdotK, the output units of the isobaric specific heat capacity CpC_p are J/kg\cdotK, and the output units of the density ρ\rho are kg/m3^3.

H-451

H-451 graphite is a near-isotropic, artificial graphite based on petroleum coke. H-451 graphite is commonly used for reflectors in nuclear applications.

Isobaric specific heat is calculated from Butland and Maddison (1973) as

Cp=4184[0.542122.42667e6T90.2725T143449.3T3+1.59309×107T31.43688×109T4]C_p=4184\left\lbrack 0.54212-2.42667e-6T-90.2725 T^{-1}-43449.3 T^{-3}+1.59309\times 10^7 T^{-3}-1.43688\times 10^9T^{-4}\right\rbrack

with a validity range of 200 K T\le T \le 3500.

The thermal conductivity is calculated from NEA (2018) as

k=3.28248×105T21.24890×101T+1.69214×102k=3.28248\times 10^{-5}T^2-1.24890\times 10^{-1}T+1.69214\times 10^2

with a validity range of 500 K T\le T \le 1800 K.

Density is taken as a constant value; a default value is provided based on NEA (2018) as

ρ=1850.0\rho=1850.0

Input Parameters

  • gradeGraphite grade

    C++ Type:MooseEnum

    Unit:(no unit assumed)

    Options:H_451

    Controllable:No

    Description:Graphite grade

Required Parameters

  • T_zero_e273.15Temperature at which the specific internal energy is assumed to be zero [K].

    Default:273.15

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:Temperature at which the specific internal energy is assumed to be zero [K].

  • allow_imperfect_jacobiansFalsetrue to allow unimplemented property derivative terms to be set to zero for the AD API

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:true to allow unimplemented property derivative terms to be set to zero for the AD API

  • density1850(Constant) density

    Default:1850

    C++ Type:double

    Unit:(no unit assumed)

    Controllable:No

    Description:(Constant) density

  • execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

    Default:TIMESTEP_END

    C++ Type:ExecFlagEnum

    Unit:(no unit assumed)

    Options:NONE, INITIAL, LINEAR, NONLINEAR_CONVERGENCE, NONLINEAR, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, FINAL, CUSTOM

    Controllable:No

    Description:The list of flag(s) indicating when this object should be executed. For a description of each flag, see https://mooseframework.inl.gov/source/interfaces/SetupInterface.html.

  • 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

    Unit:(no unit assumed)

    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.

Optional Parameters

  • allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).

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

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

    Unit:(no unit assumed)

    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

    Unit:(no unit assumed)

    Controllable:Yes

    Description:Set the enabled status of the MooseObject.

  • execution_order_group0Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

    Default:0

    C++ Type:int

    Unit:(no unit assumed)

    Controllable:No

    Description:Execution order groups are executed in increasing order (e.g., the lowest number is executed first). Note that negative group numbers may be used to execute groups before the default (0) group. Please refer to the user object documentation for ordering of user object execution within a group.

  • force_postauxFalseForces the UserObject to be executed in POSTAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in POSTAUX

  • force_preauxFalseForces the UserObject to be executed in PREAUX

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREAUX

  • force_preicFalseForces the UserObject to be executed in PREIC during initial setup

    Default:False

    C++ Type:bool

    Unit:(no unit assumed)

    Controllable:No

    Description:Forces the UserObject to be executed in PREIC during initial setup

  • 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

    Unit:(no unit assumed)

    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

References

  1. D. E. Baker. Graphite as a Neutron Moderator and Reflector Material. Nuclear Engineering and Design, 14:413–444, 1970.[BibTeX]
  2. A. T. D. Butland and R. J. Maddison. The Specific Heat of Graphite: An Evaluation of Measurements. Journal of Nuclear Materials, 49:45–56, 1973.[BibTeX]
  3. NEA. NEA Benchmark of the Modular High-Temperature Gas-Cooled Reactor-350 MW Core Design Volumes I and II. Technical Report NEA/NSC/R(2017)4, Nuclear Energy Agency, 2018.[BibTeX]