SCMMassFlowRateAux

Computes mass flow rate from specified mass flux and subchannel cross-sectional area. Can read either PostprocessorValue or Real

Overview

This is the usual kernel that the user can use to define the mass-flow rate distribution at the inlet "boundary". In addition to the boundary, the user must define the "variable" (must be mdot) and a uniform "mass_flux", which suggest a more or less uniform velocity profile at the boundary. This mass-flux can be either a Real or a Postprocessor. The mass-flow rate for each subchannel is calculated as the product of the mass-flux $var element = document.getElementById("moose-equation-5b02d976-b963-4c24-953c-80a7c8950f6c");katex.render("\\times", element, {displayMode:false,throwOnError:false});$ the surface area of each subchannel at the boundary.

Example Input File Syntax

[AuxKernels<<<{"href": "../../syntax/AuxKernels/index.html"}>>>]
  [T_in_bc]
    type = ConstantAux<<<{"description": "Creates a constant field in the domain.", "href": "ConstantAux.html"}>>>
    variable<<<{"description": "The name of the variable that this object applies to"}>>> = T
    boundary<<<{"description": "The list of boundaries (ids or names) from the mesh where this object applies"}>>> = inlet
    value<<<{"description": "Some constant value that can be read from the input file"}>>> = ${T_in}
    execute_on<<<{"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."}>>> = 'timestep_begin'
  []
  [mdot_in_bc]
    type = SCMMassFlowRateAux<<<{"description": "Computes mass flow rate from specified mass flux and subchannel cross-sectional area. Can read either PostprocessorValue or Real", "href": "SCMMassFlowRateAux.html"}>>>
    variable<<<{"description": "The name of the variable that this object applies to"}>>> = mdot
    boundary<<<{"description": "The list of boundaries (ids or names) from the mesh where this object applies"}>>> = inlet
    area<<<{"description": "Cross sectional area [m^2]"}>>> = S
    mass_flux<<<{"description": "The postprocessor or Real to use for the value of mass_flux"}>>> = ${mass_flux_in}
    execute_on<<<{"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."}>>> = 'timestep_begin'
  []
[]

Input Parameters

areaCross sectional area [m^2]
C++ Type:std::vector<VariableName>
Unit:(no unit assumed)
Controllable:No
Description:Cross sectional area [m^2]
mass_fluxThe postprocessor or Real to use for the value of mass_flux
C++ Type:PostprocessorName
Unit:(no unit assumed)
Controllable:No
Description:The postprocessor or Real to use for the value of mass_flux
variableThe name of the variable that this object applies to
C++ Type:AuxVariableName
Unit:(no unit assumed)
Controllable:No
Description:The name of the variable that this object applies to

Required 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
check_boundary_restrictedTrueWhether to check for multiple element sides on the boundary in the case of a boundary restricted, element aux variable. Setting this to false will allow contribution to a single element's elemental value(s) from multiple boundary sides on the same element (example: when the restricted boundary exists on two or more sides of an element, such as at a corner of a mesh
Default:True
C++ Type:bool
Controllable:No
Description:Whether to check for multiple element sides on the boundary in the case of a boundary restricted, element aux variable. Setting this to false will allow contribution to a single element's elemental value(s) from multiple boundary sides on the same element (example: when the restricted boundary exists on two or more sides of an element, such as at a corner of a mesh
execute_onLINEAR TIMESTEP_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:LINEAR TIMESTEP_END
C++ Type:ExecFlagEnum
Options:NONE, INITIAL, LINEAR, LINEAR_CONVERGENCE, NONLINEAR, NONLINEAR_CONVERGENCE, POSTCHECK, TIMESTEP_END, TIMESTEP_BEGIN, MULTIAPP_FIXED_POINT_END, MULTIAPP_FIXED_POINT_BEGIN, MULTIAPP_FIXED_POINT_CONVERGENCE, FINAL, CUSTOM, PRE_DISPLACE
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.

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.
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

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

(moose/modules/subchannel/validation/psbt/psbt_ss/psbt.i)

# M. Avramova et al., 2012,
# OECD/NRC Benchmark Based on NUPEC PWR
# Sub-channel and Bundle Tests (PSBT). Volume III: Departure from Nucleate Boiling
# Case:01-5237
T_in = 502.35
# [1e+6 kg/m^2-hour] turns into kg/m^2-sec
mass_flux_in = ${fparse 1e+6 * 16.95 / 3600.}
P_out = 14.72e6 # Pa
[QuadSubChannelMesh]
  [sub_channel]
    type = SCMQuadSubChannelMeshGenerator
    nx = 6
    ny = 6
    n_cells = 20
    pitch = 0.0126
    pin_diameter = 0.00950
    gap = 0.00095
    heated_length = 3.658
    spacer_z = '0.0 0.229 0.457 0.686 0.914 1.143 1.372 1.600 1.829 2.057 2.286 2.515 2.743 2.972 3.200 3.429'
    spacer_k = '0.7 0.4 1.0 0.4 1.0 0.4 1.0 0.4 1.0 0.4 1.0 0.4 1.0 0.4 1.0 0.4'
  []

  [fuel_pins]
    type = SCMQuadPinMeshGenerator
    input = sub_channel
    nx = 6
    ny = 6
    n_cells = 20
    pitch = 0.0126
    heated_length = 3.658
  []
[]

[AuxVariables]
  [mdot]
    block = sub_channel
  []
  [SumWij]
    block = sub_channel
  []
  [P]
    block = sub_channel
  []
  [DP]
    block = sub_channel
  []
  [h]
    block = sub_channel
  []
  [T]
    block = sub_channel
  []
  [Tpin]
    block = fuel_pins
  []
  [rho]
    block = sub_channel
  []
  [mu]
    block = sub_channel
  []
  [S]
    block = sub_channel
  []
  [w_perim]
    block = sub_channel
  []
  [q_prime]
    block = fuel_pins
  []
[]

[FluidProperties]
  [water]
    type = Water97FluidProperties
  []
[]

[SubChannel]
  type = QuadSubChannel1PhaseProblem
  fp = water
  n_blocks = 1
  beta = 0.08
  CT = 2.6
  compute_density = true
  compute_viscosity = true
  compute_power = true
  P_out = ${P_out}
  implicit = true
  segregated = false
  staggered_pressure = false
  monolithic_thermal = false
  verbose_subchannel = true
  interpolation_scheme = exponential
  deformation = true # this flag allows the re-calculation of subchannel geometric parameters based on the dpin value
[]

[ICs]
  [S_IC]
    type = SCMQuadFlowAreaIC
    variable = S
  []

  [w_perim_IC]
    type = SCMQuadWettedPerimIC
    variable = w_perim
  []

  [q_prime_IC]
    type = SCMQuadPowerIC
    variable = q_prime
    power = 3.23e6 # W
    filename = "power_profile.txt"
  []

  [T_ic]
    type = ConstantIC
    variable = T
    value = ${T_in}
  []

  [Dpin_ic]
    type = ConstantIC
    variable = Dpin
    value = 0.00950
  []

  [P_ic]
    type = ConstantIC
    variable = P
    value = 0.0
  []

  [DP_ic]
    type = ConstantIC
    variable = DP
    value = 0.0
  []

  [Viscosity_ic]
    type = ViscosityIC
    variable = mu
    p = ${P_out}
    T = T
    fp = water
  []

  [rho_ic]
    type = RhoFromPressureTemperatureIC
    variable = rho
    p = ${P_out}
    T = T
    fp = water
  []

  [h_ic]
    type = SpecificEnthalpyFromPressureTemperatureIC
    variable = h
    p = ${P_out}
    T = T
    fp = water
  []

  [mdot_ic]
    type = ConstantIC
    variable = mdot
    value = 0.0
  []
[]

[AuxKernels]
  [T_in_bc]
    type = ConstantAux
    variable = T
    boundary = inlet
    value = ${T_in}
    execute_on = 'timestep_begin'
  []
  [mdot_in_bc]
    type = SCMMassFlowRateAux
    variable = mdot
    boundary = inlet
    area = S
    mass_flux = ${mass_flux_in}
    execute_on = 'timestep_begin'
  []
[]

[Outputs]
  exodus = true
  csv = true
  [Temp_Out_MATRIX]
    type = QuadSubChannelNormalSliceValues
    variable = T
    execute_on = final
    file_base = "Temp_Out.txt"
    height = 3.658
  []
  [mdot_Out_MATRIX]
    type = QuadSubChannelNormalSliceValues
    variable = mdot
    execute_on = final
    file_base = "mdot_Out.txt"
    height = 3.658
  []
  [mdot_In_MATRIX]
    type = QuadSubChannelNormalSliceValues
    variable = mdot
    execute_on = final
    file_base = "mdot_In.txt"
    height = 0.0
  []
[]

[Postprocessors]
  [total_pressure_drop]
    type = SubChannelDelta
    variable = P
    execute_on = "timestep_end"
  []
  [T1]
    type = SubChannelPointValue
    variable = T
    index = 0
    execute_on = "timestep_end"
    height = 3.658
  []
  [T2]
    type = SubChannelPointValue
    variable = T
    index = 7
    execute_on = "timestep_end"
    height = 3.658
  []
  [T3]
    type = SubChannelPointValue
    variable = T
    index = 14
    execute_on = "timestep_end"
    height = 3.658
  []
  [T4]
    type = SubChannelPointValue
    variable = T
    index = 21
    execute_on = "timestep_end"
    height = 3.658
  []
  [T5]
    type = SubChannelPointValue
    variable = T
    index = 28
    execute_on = "timestep_end"
    height = 3.658
  []
  [T6]
    type = SubChannelPointValue
    variable = T
    index = 35
    execute_on = "timestep_end"
    height = 3.658
  []
  [PinTemp]
    type = SCMPinSurfaceTemperature
    index = 10
    height = 3.658
  []
[]

[Executioner]
  type = Steady
[]

Overview
Example Input File Syntax
Input Parameters