SCMQuadAssemblyMeshGenerator

Creates one mesh containing both 1D subchannels and 1D pins in a square lattice arrangement

Overview

This mesh generator creates the 1D subchannel and pin meshes for a square lattice arrangement. The generated subdomains are named subchannel and fuel_pins. The center of the mesh is the origin.

This object replaces the old chained SCMQuadSubChannelMeshGenerator and SCMQuadPinMeshGenerator input pattern. See the SubChannel mesh generator migration page for old-to-new input examples.

Example Input File Syntax

[QuadSubChannelMesh<<<{"href": "../../syntax/QuadSubChannelMesh/index.html"}>>>]
  [sub_channel]
    type = SCMQuadAssemblyMeshGenerator<<<{"description": "Creates one mesh containing both 1D subchannels and 1D pins in a square lattice arrangement", "href": "SCMQuadAssemblyMeshGenerator.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"}>>> = 10
    pitch<<<{"description": "Pitch [m]"}>>> = 0.0126
    pin_diameter<<<{"description": "Rod diameter [m]"}>>> = ${pin_diameter}
    side_gap<<<{"description": "The side gap, not to be confused with the gap between pins; this refers to the gap next to the duct or else the distance between the subchannel centroid and the duct wall. distance(edge pin center, duct wall) = pitch / 2 + side_gap [m]"}>>> = 0.00095
    heated_length<<<{"description": "Heated length [m]"}>>> = 1.0
    spacer_z<<<{"description": "Axial location of spacers/vanes/mixing vanes [m]"}>>> = '0.0'
    spacer_k<<<{"description": "K-loss coefficient of spacers/vanes/mixing vanes [-]"}>>> = '0.0'
  []
[]

Input Parameters

heated_lengthHeated length [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Heated length [m]
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 channels in the x direction [-]
C++ Type:unsigned int
Controllable:No
Description:Number of channels in the x direction [-]
nyNumber of channels in the y direction [-]
C++ Type:unsigned int
Controllable:No
Description:Number of channels in the y direction [-]
pin_diameterRod diameter [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Rod diameter [m]
pitchPitch [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Pitch [m]
side_gapThe side gap, not to be confused with the gap between pins; this refers to the gap next to the duct or else the distance between the subchannel centroid and the duct wall. distance(edge pin center, duct wall) = pitch / 2 + side_gap [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:The side gap, not to be confused with the gap between pins; this refers to the gap next to the duct or else the distance between the subchannel centroid and the duct wall. distance(edge pin center, duct wall) = pitch / 2 + side_gap [m]

Required Parameters

Kij0.5Lateral form loss coefficient [-]
Default:0.5
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Lateral form loss coefficient [-]
index_blockage0 Index of subchannels affected by blockage
Default:0
C++ Type:std::vector<unsigned int>
Controllable:No
Description:Index of subchannels affected by blockage
k_blockage0 Form loss coefficient of blocked subchannels
Default:0
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Form loss coefficient of blocked subchannels
pin_block_id1Fuel Pin block id
Default:1
C++ Type:unsigned int
Controllable:No
Description:Fuel Pin block id
reduction_blockage1 Area reduction of subchannels affected by blockage
Default:1
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Area reduction of subchannels affected by blockage
spacer_kK-loss coefficient of spacers/vanes/mixing vanes [-]
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:K-loss coefficient of spacers/vanes/mixing vanes [-]
spacer_zAxial location of spacers/vanes/mixing vanes [m]
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Axial location of spacers/vanes/mixing vanes [m]
subchannel_block_id0Subchannel block id
Default:0
C++ Type:unsigned int
Controllable:No
Description:Subchannel block id
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]
z_blockage0 0 Axial location of blockage (inlet, outlet) [m]
Default:0 0
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Axial location of blockage (inlet, outlet) [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

(contrib/moose/modules/subchannel/test/tests/problems/psbt/psbt_explicit.i)

T_in = 359.15
# [1e+6 kg/m^2-hour] turns into kg/m^2-sec
mass_flux_in = '${fparse 1e+6 * 17.00 / 3600.}'
P_out = 4.923e6 # Pa
pin_diameter = 0.00950

[QuadSubChannelMesh]
  [sub_channel]
    type = SCMQuadAssemblyMeshGenerator
    nx = 6
    ny = 6
    n_cells = 10
    pitch = 0.0126
    pin_diameter = ${pin_diameter}
    side_gap = 0.00095
    heated_length = 1.0
    spacer_z = '0.0'
    spacer_k = '0.0'
  []
[]

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

[SubChannel]
  type = QuadSubChannel1PhaseProblem
  fp = water
  n_blocks = 1
  compute_density = true
  compute_viscosity = true
  compute_power = true
  P_out = ${P_out}
  verbose_subchannel = true
  friction_closure = 'MATRA'
  pin_HTC_closure = 'Dittus-Boelter'
  full_output = true
  mixing_closure ='constant_beta'
[]

[SCMClosures]
  [MATRA]
    type = SCMFrictionMATRA
  []
  [Dittus-Boelter]
    type = SCMHTCDittusBoelter
  []
  [constant_beta]
    type = SCMMixingConstantBeta
    beta = 0.006
    CT = 2.6
  []
[]

[ICs]


  [q_prime_IC]
    type = SCMQuadPowerIC
    variable = q_prime
    power = 1.0e6 # W
    filename = "power_profile.txt" #type in name of file that describes radial power profile
    block = fuel_pins
  []

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


  [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'
    block = subchannel
  []
  [mdot_in_bc]
    type = SCMMassFlowRateAux
    variable = mdot
    boundary = inlet
    area = S
    mass_flux = report_mass_flux_inlet
    execute_on = 'timestep_begin'
    block = subchannel
  []
[]

[Postprocessors]
  [report_mass_flux_inlet]
    type = Receiver
    default = ${mass_flux_in}
  []
  [total_pressure_drop]
    type = SubChannelDelta
    variable = P
    execute_on = "timestep_end"
  []
  [T1]
    type = SubChannelPointValue
    variable = T
    index = 0
    execute_on = "timestep_end"
    height = 1
  []
  [T2]
    type = SubChannelPointValue
    variable = T
    index = 7
    execute_on = "timestep_end"
    height = 1
  []
  [T3]
    type = SubChannelPointValue
    variable = T
    index = 14
    execute_on = "timestep_end"
    height = 1
  []
  [T4]
    type = SubChannelPointValue
    variable = T
    index = 21
    execute_on = "timestep_end"
    height = 1
  []
  [T5]
    type = SubChannelPointValue
    variable = T
    index = 28
    execute_on = "timestep_end"
    height = 1
  []
  [T6]
    type = SubChannelPointValue
    variable = T
    index = 35
    execute_on = "timestep_end"
    height = 1
  []
[]

[Outputs]
  csv = true
[]

[Executioner]
  type = Steady
[]

Overview
Example Input File Syntax
Input Parameters