SCMTriSubChannelMeshGenerator

Creates a mesh of 1D subchannels in a triangular lattice arrangement

Overview

This mesh generator creates the mesh were the SCM solution variables associated with the subchannels live. The user needs to provide the "nrings" parameter which defines the number of fuel pin rings. For triangular sub-assemblies, one nring means that there is one central pin in the (0 0 0) position and six neighboring ones on the the vertices of a normal hexagon. 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 sub-assembly in the -z direction is defined by the parameters: "heated_length","unheated_length_entry","unheated_length_entry". The fuel pin diameter is given by "pin_diameter". The user also has the ability to define the effect of spacers or mixing vanes on the sub-assembly by defining their axial location "spacer_z" and a local presure from loss "spacer_k". "flat_to_flat" is the size of the hexagonal duct that encloses the sub-assembly. If the pins are wire wrapped then the parameters: "dwire" "hwire" have non zero values that describe the geometry of the wire-wrap. The center of the mesh is the origin.

Example Input File Syntax

[TriSubChannelMesh<<<{"href": "../../syntax/TriSubChannelMesh/index.html"}>>>]
  [subchannel]
    type = SCMTriSubChannelMeshGenerator<<<{"description": "Creates a mesh of 1D subchannels in a triangular lattice arrangement", "href": "SCMTriSubChannelMeshGenerator.html"}>>>
    nrings<<<{"description": "Number of fuel Pin rings per assembly [-]"}>>> = 4
    n_cells<<<{"description": "The number of cells in the axial direction"}>>> = 20
    flat_to_flat<<<{"description": "Flat to flat distance for the hexagonal assembly [m]"}>>> = 0.085
    heated_length<<<{"description": "Heated length [m]"}>>> = 1.0
    pin_diameter<<<{"description": "Rod diameter [m]"}>>> = 0.01
    pitch<<<{"description": "Pitch [m]"}>>> = 0.012
    dwire<<<{"description": "Wire diameter [m]"}>>> = 0.002
    hwire<<<{"description": "Wire lead length [m]"}>>> = 0.0833
    spacer_z<<<{"description": "Axial location of spacers/vanes/mixing_vanes [m]"}>>> = '0 0.2 0.4 0.6 0.8'
    spacer_k<<<{"description": "K-loss coefficient of spacers/vanes/mixing_vanes [-]"}>>> = '0.1 0.1 0.1 0.1 0.10'
  []
[]

Input Parameters

dwireWire diameter [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Wire diameter [m]
flat_to_flatFlat to flat distance for the hexagonal assembly [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Flat to flat distance for the hexagonal assembly [m]
heated_lengthHeated length [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Heated length [m]
hwireWire lead length [m]
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Wire lead 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
nringsNumber of fuel Pin rings per assembly [-]
C++ Type:unsigned int
Controllable:No
Description:Number of fuel Pin rings per assembly [-]
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]

Required Parameters

Kij0.5Lateral form loss coefficient [-]
Default:0.5
C++ Type:double
Unit:(no unit assumed)
Controllable:No
Description:Lateral form loss coefficient [-]
block_id0Domain Index
Default:0
C++ Type:unsigned int
Controllable:No
Description:Domain Index
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 subchannels affected by blockage
Default:0
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Form loss coefficient of subchannels affected by blockage
reduction_blockage1 Area reduction of subchannels affected by blockage (number to muliply the area)
Default:1
C++ Type:std::vector<double>
Unit:(no unit assumed)
Controllable:No
Description:Area reduction of subchannels affected by blockage (number to muliply the area)
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]
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

(moose/modules/subchannel/validation/Toshiba_37_pin/toshiba_37_pin.i)

T_in = 660
# [1e+6 kg/m^2-hour] turns into kg/m^2-sec
mass_flux_in = '${fparse 1e+6 * 37.00 / 36000.*0.5}'
P_out = 2.0e5 # Pa
[TriSubChannelMesh]
  [subchannel]
    type = SCMTriSubChannelMeshGenerator
    nrings = 4
    n_cells = 20
    flat_to_flat = 0.085
    heated_length = 1.0
    pin_diameter = 0.01
    pitch = 0.012
    dwire = 0.002
    hwire = 0.0833
    spacer_z = '0 0.2 0.4 0.6 0.8'
    spacer_k = '0.1 0.1 0.1 0.1 0.10'
  []
[]

[AuxVariables]
  [mdot]
  []
  [SumWij]
  []
  [P]
  []
  [DP]
  []
  [h]
  []
  [T]
  []
  [rho]
  []
  [S]
  []
  [w_perim]
  []
  [q_prime]
  []
  [mu]
  []
  [displacement]
  []
[]

[FluidProperties]
  [sodium]
    type = PBSodiumFluidProperties
  []
[]

[Problem]
  type = TriSubChannel1PhaseProblem
  fp = sodium
  n_blocks = 1
  P_out = 2.0e5
  CT = 1.0
  compute_density = true
  compute_viscosity = true
  compute_power = true
  P_tol = 1.0e-6
  T_tol = 1.0e-3
  implicit = true
  segregated = false
  staggered_pressure = false
  monolithic_thermal = false
  verbose_multiapps = true
  verbose_subchannel = false
[]

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

  [w_perim_IC]
    type = SCMTriWettedPerimIC
    variable = w_perim
  []

  [q_prime_IC]
    type = SCMTriPowerIC
    variable = q_prime
    power = 1.000e5 # W
    filename = "pin_power_profile_37.txt"
  []

  [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 = sodium
  []

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

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

  [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
[]

[Executioner]
  type = Steady
[]

[Postprocessors]
  [T_Planar_Mean]
    type = SCMPlanarMean
    variable = T
    execute_on = 'TIMESTEP_END'
    height = 1.0
  []

  [DP_SubchannelDelta]
    type = SubChannelDelta
    variable = P
    execute_on = 'TIMESTEP_END'
  []
[]
################################################################################
# A multiapp that projects data to a detailed mesh
################################################################################

[MultiApps]
  [viz]
    type = FullSolveMultiApp
    input_files = "toshiba_37_pin_viz.i"
    execute_on = "timestep_end"
  []
[]

[Transfers]
  [xfer]
    type = SCMSolutionTransfer
    to_multi_app = viz
    variable = 'mdot SumWij P DP h T rho mu q_prime S'
  []
[]

Overview
Example Input File Syntax
Input Parameters