SCMQuadPinMeshGenerator

Creates a mesh of 1D fuel pins in a square lattice arrangement

Overview

This mesh generator creates the mesh were the SCM solution variables associated with the fuel pins live. The user needs to provide the number of subchannels "nx" in the -x direction and "ny" in the -y direction. The number of cells in the -z direction is given by "n_cells". The distance of the pins from eachother is given by the "pitch" parameter and the total length of the pins in the -z direction is defined by the parameters: "heated_length","unheated_length_entry","unheated_length_exit". Last, "input" is a parameter that takes the name of an object of type SCMQuadSubChannelMeshGenerator so the user must be careful to define consistent parameters across both MeshGenerators. The center of the mesh is the origin.

Example Input File Syntax

[QuadSubChannelMesh<<<{"href": "../../syntax/QuadSubChannelMesh/index.html"}>>>]
  [sub_channel]
    type = SCMQuadSubChannelMeshGenerator<<<{"description": "Creates a mesh of 1D subchannels in a square lattice arrangement", "href": "SCMQuadSubChannelMeshGenerator.html"}>>>
    nx<<<{"description": "Number of channels in the x direction [-]"}>>> = 6
    ny<<<{"description": "Number of channels in the y direction [-]"}>>> = 6
    n_cells<<<{"description": "The number of cells in the axial direction"}>>> = 20
    pitch<<<{"description": "Pitch [m]"}>>> = 0.0126
    pin_diameter<<<{"description": "Rod diameter [m]"}>>> = 0.00950
    gap<<<{"description": "(Its an added distance between a perimetric pin and the duct: Edge Pitch W = (pitch/2 - pin_diameter/2 + gap) [m]"}>>> = 0.00095
    heated_length<<<{"description": "Heated length [m]"}>>> = 3.658
    spacer_z<<<{"description": "Axial location of spacers/vanes/mixing_vanes [m]"}>>> = '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<<<{"description": "K-loss coefficient of spacers/vanes/mixing_vanes [-]"}>>> = '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<<<{"description": "Creates a mesh of 1D fuel pins in a square lattice arrangement", "href": "SCMQuadPinMeshGenerator.html"}>>>
    input<<<{"description": "The corresponding subchannel mesh"}>>> = sub_channel
    nx<<<{"description": "Number of subchannels in the x direction [-]"}>>> = 6
    ny<<<{"description": "Number of subchannels in the y direction [-]"}>>> = 6
    n_cells<<<{"description": "The number of cells in the axial direction"}>>> = 20
    pitch<<<{"description": "Pitch [m]"}>>> = 0.0126
    heated_length<<<{"description": "Heated length [m]"}>>> = 3.658
  []
[]

Input Parameters

heated_lengthHeated length [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Heated length [m]
inputThe corresponding subchannel mesh
C++ Type:MeshGeneratorName
Controllable:No
Description:The corresponding subchannel mesh
n_cellsThe number of cells in the axial direction
C++ Type:unsigned int
Controllable:No
Description:The number of cells in the axial direction
nxNumber of subchannels in the x direction [-]
C++ Type:unsigned int
Controllable:No
Description:Number of subchannels in the x direction [-]
nyNumber of subchannels in the y direction [-]
C++ Type:unsigned int
Controllable:No
Description:Number of subchannels in the y direction [-]
pitchPitch [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Pitch [m]

Required Parameters

block_id1Domain Index
Default:1
C++ Type:unsigned int
Controllable:No
Description:Domain Index
unheated_length_entry0Unheated length at entry [m]
Default:0
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Unheated length at entry [m]
unheated_length_exit0Unheated length at exit [m]
Default:0
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Unheated length at exit [m]

Optional Parameters

enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Controllable:No
Description:Set the enabled status of the MooseObject.
save_with_nameKeep the mesh from this mesh generator in memory with the name specified
C++ Type:std::string
Controllable:No
Description:Keep the mesh from this mesh generator in memory with the name specified

Advanced Parameters

nemesisFalseWhether or not to output the mesh file in the nemesisformat (only if output = true)
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to output the mesh file in the nemesisformat (only if output = true)
outputFalseWhether or not to output the mesh file after generating the mesh
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to output the mesh file after generating the mesh
show_infoFalseWhether or not to show mesh info after generating the mesh (bounding box, element types, sidesets, nodesets, subdomains, etc)
Default:False
C++ Type:bool
Controllable:No
Description:Whether or not to show mesh info after generating the mesh (bounding box, element types, sidesets, nodesets, subdomains, etc)

Debugging 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