SimpleHexagonGenerator

This SimpleHexagonGenerator object is designed to generate a simple hexagonal mesh that only contains six simple azimuthal triangular elements, two quadrilateral elements, or six central azimuthal triangular elements plus a several layers of quadrilateral elements.

Overview

SimpleHexagonGenerator is a simple version of PolygonConcentricCircleMeshGenerator. This mesh generator meshes a simple hexagon with no pin. This mesh generator is commonly used to mesh homogenized pins or assemblies with either 6 triangular elements (default option, "element_type" as TRI) or 2 quadrilateral elements ("element_type" as QUAD, see Figure 2). No additional azimuthal or radial discretizations are permitted with these two options.

A third option is available to introduce additional radial layers in the form of concentric hexagonal zones using "element_type" as HYBRID. In that case, the azimuthal discretization is identical to the TRI case (num_sectors_per_side = {1, 1, 1, 1, 1, 1}) but the mesh can now have multiple radial layers of elements (i.e. triangular elements in the center and quadrilateral elements in the outer layers as shown in Figure 3). The number of layers is specified by "radial_intervals". It is important to note that this option creates two separate subdomains (one for TRI elements, one for QUAD elements), and requires two separate subdomain IDs rather than one.

A schematic drawing showing a typical simple hexagonal mesh generated by this `SimpleHexagonGenerator` object with [!param](/Mesh/SimpleHexagonGenerator/element_type) as `TRI`.

Figure 1: A schematic drawing showing a typical simple hexagonal mesh generated by this SimpleHexagonGenerator object with "element_type" as TRI.

A hexagonal mesh generated by `SimpleHexagonGenerator` with [!param](/Mesh/SimpleHexagonGenerator/element_type) as `QUAD`.

Figure 2: A hexagonal mesh generated by SimpleHexagonGenerator with "element_type" as QUAD.

A hexagonal mesh generated by `SimpleHexagonGenerator` with [!param](/Mesh/SimpleHexagonGenerator/element_type) as `HYBRID` (note the additional radial discretizations).

Figure 3: A hexagonal mesh generated by SimpleHexagonGenerator with "element_type" as HYBRID (note the additional radial discretizations).

This mesh generator creates the same MeshMetaData as PolygonConcentricCircleMeshGenerator. The produced mesh can be used as inputs to PatternedHexMeshGenerator.

Example Syntax

[Mesh<<<{"href": "../../syntax/Mesh/index.html"}>>>]
  [shg]
    type = SimpleHexagonGenerator<<<{"description": "This SimpleHexagonGenerator object is designed to generate a simple hexagonal mesh that only contains six simple azimuthal triangular elements, two quadrilateral elements, or six central azimuthal triangular elements plus a several layers of quadrilateral elements.", "href": "SimpleHexagonGenerator.html"}>>>
    hexagon_size<<<{"description": "Size of the hexagon to be generated."}>>> = 1.0
    block_id<<<{"description": "Optional customized block id; two ids are needed for HYBRID 'element_type'."}>>> = 100
    block_name<<<{"description": "Optional customized block name; two names are needed for HYBRID 'element_type'."}>>> = hexagon
    external_boundary_id<<<{"description": "Optional customized external boundary id."}>>> = 300
    external_boundary_name<<<{"description": "Optional customized external boundary name."}>>> = 'external_side'
  []
[]

Input Parameters

hexagon_sizeSize of the hexagon to be generated.
C++ Type:Real
Unit:(no unit assumed)
Range:hexagon_size>0.0
Controllable:No
Description:Size of the hexagon to be generated.

Required Parameters

element_typeTRIWhether the simple hexagon mesh is made of TRI or QUAD elements.
Default:TRI
C++ Type:MooseEnum
Options:TRI, QUAD, HYBRID
Controllable:No
Description:Whether the simple hexagon mesh is made of TRI or QUAD elements.
hexagon_size_styleapothemStyle in which the hexagon size is given (default: apothem i.e. half-pitch). Option: apothem radius
Default:apothem
C++ Type:MooseEnum
Options:apothem, radius
Controllable:No
Description:Style in which the hexagon size is given (default: apothem i.e. half-pitch). Option: apothem radius
radial_intervalsNumber of pin radial meshing rings (only applicable when 'element_type' is 'HYBRID').
C++ Type:unsigned int
Range:radial_intervals>1
Controllable:No
Description:Number of pin radial meshing rings (only applicable when 'element_type' is 'HYBRID').

Optional Parameters

block_idOptional customized block id; two ids are needed for HYBRID 'element_type'.
C++ Type:std::vector<unsigned short>
Range:block_id>=0
Controllable:No
Description:Optional customized block id; two ids are needed for HYBRID 'element_type'.
block_nameOptional customized block name; two names are needed for HYBRID 'element_type'.
C++ Type:std::vector<SubdomainName>
Controllable:No
Description:Optional customized block name; two names are needed for HYBRID 'element_type'.
external_boundary_idOptional customized external boundary id.
C++ Type:short
Range:external_boundary_id>=0
Controllable:No
Description:Optional customized external boundary id.
external_boundary_nameOptional customized external boundary name.
C++ Type:BoundaryName
Controllable:No
Description:Optional customized external boundary name.

Customized Subdomain/Boundary 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

Input Files

(tutorials/tutorial04_meshing/app/test/tests/base_mesh_generators/common_geo.i)
(modules/reactor/test/tests/meshgenerators/patterned_hex_mesh_generator/sim_patterned.i)
(modules/reactor/test/tests/meshgenerators/revolve_generator/simple_revolve.i)
(tutorials/tutorial04_meshing/app/test/tests/reactor_examples/abtr/abtr.i)
(modules/reactor/test/tests/meshgenerators/revolve_generator/multi_revolve.i)
(modules/reactor/test/tests/meshgenerators/simple_hexagon_generator/sim_hex.i)
(modules/reactor/test/tests/meshgenerators/reporting_id/hexagonal_id/core_reporting_id_exclude.i)
(modules/reactor/test/tests/meshgenerators/flexible_pattern_generator/double_ext_boundary.i)
(tutorials/tutorial04_meshing/app/test/tests/adv_examples/mesh_revolve.i)

(modules/reactor/test/tests/meshgenerators/simple_hexagon_generator/sim_hex.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = 100
    block_name = hexagon
    external_boundary_id  = 300
    external_boundary_name = 'external_side'
  []
[]

(tutorials/tutorial04_meshing/app/test/tests/base_mesh_generators/common_geo.i)

# Uncomment on of the following `final_mg` definition to run
# the corresponding demonstration.

[Mesh]
   # Select the final generator to be used for this run
  ## PCCMG Demo
  #final_generator = 'hex_1'
  ## PatternedHexMeshGenerator Demo for Assembly
  #final_generator = 'pattern_assm'
  ## Simple Hex Assembly Demo
  #final_generator = 'hex_simple'
  ## Side Trimming Demo
  #final_generator = 'pattern_assm_peri_trim'
  ## Assembly Peripheral Modification Demo
  #final_generator = 'pattern_assm_peri_mod'
  ## Adaptive Assembly Demo
  #final_generator = 'adaptive_assm'
  ## Core Mesh Generation Demo
  #final_generator = 'pattern_core'
  ## Core Peripheral Ring Demo
  #final_generator = 'pr'
  ## Core Peripheral Triagular Ring Demo
  #final_generator = 'pt'
  ## Core Azimuthal Trimming Demo
  #final_generator = 'core_trim'
  ## Extrusion Demo
  final_generator = 'core_ext'

  # PCCMG to generate a pin cell
  [hex_1]
    type = PolygonConcentricCircleMeshGenerator
    # General parameters
    num_sides = 6
    num_sectors_per_side = '4 4 4 4 4 4'
    polygon_size = 5.0
    # Ring regions parameters
    ring_radii = 4.0
    ring_intervals = 2
    ring_block_ids = '10 15'
    ring_block_names = 'center_tri center'
    preserve_volumes = on
    # Background region parameters
    background_intervals = 2
    background_block_ids = 20
    background_block_names = background
#    # Optional Duct regions parameters
#    duct_sizes = '4.5 4.8'
#    duct_sizes_style = apothem
#    duct_block_ids = '22 24'
#    duct_block_names = 'duct_in duct_out'
#    duct_intervals = '1 2'
  []

  # PHMG to combine pins into an assembly
  [pattern_assm]
    type = PatternedHexMeshGenerator
    inputs = 'hex_1'
    pattern = '0 0;
              0 0 0;
               0 0'
    hexagon_size = 16
    # Background region parameters
    background_intervals = 2
    background_block_id = 80
    background_block_name = hex_background
#    # Optional Duct regions parameters
#    duct_sizes = '15.0 15.5'
#    duct_sizes_style = apothem
#    duct_block_ids = '82 84'
#    duct_block_names = 'assm_duct_in assm_duct_out'
#    duct_intervals = '1 2'
    # Advanced option
    deform_non_circular_region = false
  []

  # HMT to remove the outmost layer of the assembly to expose half pins
  [pattern_assm_peri_trim]
    type = HexagonMeshTrimmer
    input = pattern_assm
    trim_peripheral_region = '1 1 1 1 1 1'
    peripheral_trimming_section_boundary = peripheral_section
  []

  # PHPM to modify the outmost layer of the assembly to specify
  # the node number on the external boundary and facilitate stitching disimilar assemblies
  [pattern_assm_peri_mod]
    type = PatternedHexPeripheralModifier
    input = pattern_assm
    input_mesh_external_boundary = 10000
    new_num_sector = 10
    num_layers = 2
  []

  # HCCABMG to generate a PCCMG-style reflector/control drum assembly compatible with
  # ordinary assemblies generated by PHMG
  [adaptive_assm]
    type = HexagonConcentricCircleAdaptiveBoundaryMeshGenerator
    num_sectors_per_side = '4 4 4 4 4 4'
    background_intervals = 2
    hexagon_size = 16
    sides_to_adapt = '1 2 3'
    meshes_to_adapt_to = 'pattern_assm pattern_assm pattern_assm'
  []

  # SHG to generate simple (coarse) assembly mesh
  [hex_simple]
    type = SimpleHexagonGenerator
    hexagon_size = 16
    # Options: TRI, QUAD, HYBRID
    element_type = TRI
    # Optional subdomain id/name
    block_id = '100'
    block_name = 'hexagon'
  []

  # PHMG to combine assembly mesh into a core mesh
  [pattern_core]
    type = PatternedHexMeshGenerator
    inputs = 'pattern_assm adaptive_assm'
    pattern_boundary = none
    # Set as true to tell MOOSE that inputs have meshes made by PatternedHexMeshGenerator
    # Set as false if the inputs are made by SimpleHexagonGenerator
    generate_core_metadata = true
    pattern = '0 0 0;
              0 0 0 0;
             0 0 0 0 1;
              0 0 0 0;
               0 0 0'
  []

  # PRMG to add a circular peripheral region for the core mesh
  [pr]
    type = PeripheralRingMeshGenerator
    input = pattern_core
    peripheral_layer_num = 3
    peripheral_ring_radius = 100.0
    input_mesh_external_boundary = 10000
    peripheral_ring_block_id = 300
    peripheral_ring_block_name = reactor_ring
  []

  # PTMG to add a circular peripheral region for the core mesh
  [pt]
    type = PeripheralTriangleMeshGenerator
    input = pattern_core
    peripheral_ring_radius = 100.0
    peripheral_ring_num_segments = 100
    desired_area = 20
  []

  # HMT to trim an azimuthal slice from the full 2D core mesh
  [core_trim]
    type = HexagonMeshTrimmer
    input = pr
    center_trim_starting_index = 0
    center_trim_ending_index = 2
    center_trimming_section_boundary = symmetric
  []

  # AEG to extrude the 2D mesh into 3D
  [core_ext]
    type = AdvancedExtruderGenerator
    input = core_trim
    heights = '30 60 30'
    num_layers = '2 3 2'
    direction = '0 0 1'
    # Optional subdomain swap
    subdomain_swaps = '10 100 15 150 20 150 80 150 300 150;
                        ;
                       10 200 15 250 20 250 80 250 300 250'
  []
[]

(modules/reactor/test/tests/meshgenerators/patterned_hex_mesh_generator/sim_patterned.i)

[Mesh]
  [hex_1]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = 1000
    block_name = hex_1000
  []
  [pattern]
    type = PatternedHexMeshGenerator
    inputs = 'hex_1'
    pattern = '0 0;
              0 0 0;
               0 0'
    pattern_boundary = none
  []
[]

(modules/reactor/test/tests/meshgenerators/revolve_generator/simple_revolve.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = 100
    block_name = hexagon
    external_boundary_id  = 300
    external_boundary_name = 'external_side'
  []
  [rg]
    type = RevolveGenerator
    input = shg
    axis_point = '5.0 0.0 0.0'
    axis_direction = '0.0 1.0 0.0'
    nums_azimuthal_intervals = 6
  []
[]

(tutorials/tutorial04_meshing/app/test/tests/reactor_examples/abtr/abtr.i)

# Advanced Burner Test Reactor - 3D Core with Homogeneous Assemblies


[Mesh]

  #################################      # This parameter allows us to execute the file but stop at this block so we can see intermediate output.
  final_generator = abtr_mesh            # User: Change this to control, dummy, core, del_dummy, extrude, plane_id, or abtr_mesh
  ################################

  # step 1: control
  # step 2: dummy
  # step 3: core
  # step 4: del_dummy
  # step 5: extrude
  # step 6: plane_id
  # step 7: abtr_mesh

  ### Step 1. Define homogeneous assembly types
  # There are 7 unique assembly types in the core. All assemblies of a given type will be considered the same in terms of materials/cross sections.

  [control]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425 # Half of the assembly pitch, which is 14.685
    hexagon_size_style = 'apothem'   # default
    element_type = QUAD
    block_id = '0'
  []
  [inner_core]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '1'
  []
  [test_fuel]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '2'
  []
  [inner_reflector]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '3'
  []
  [outer_core]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '4'
  []
  [outer_reflector]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '5'
  []
  [shield]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '6'
  []

  ### Step 2. Define dummy assembly type
  ### Dummy assemblies are needed only to make a perfect hex pattern and will be deleted later. Note the assignment of block 997.

  [dummy]
    type = SimpleHexagonGenerator
    hexagon_size = 7.3425
    hexagon_size_style = 'apothem'
    element_type = QUAD
    block_id = '997'
  []


  ### Step 3. Pattern assemblies into a perfect grid by using dummy assemblies to fill in empty slots.

  [core]
    type = PatternedHexMeshGenerator
    inputs = 'control inner_core test_fuel inner_reflector
              outer_core outer_reflector shield dummy'
    pattern_boundary = none           # do not add background coolant or a duct around this pattern
    rotate_angle = 0                  # do not rotate (default is 90 degrees, i.e. vertex up)
    external_boundary_name = radial   # external boundary is called 'radial'
    generate_core_metadata = false    # This is a special case. Even though this is a core, we say "false" since the assemblies
                                      # are homogenized (no pin information) and this is the first invocation of patterning.

    pattern =   '  7   7   6   6   6   6   6   6   7   7;
                 7   6   6   5   5   5   5   5   6   6   7;
               6   6   5   5   3   3   3   3   5   5   6   6;
             6   5   5   3   3   3   3   3   3   3   5   5   6;
           6   5   3   3   3   3   4   4   3   3   3   3   5   6;
         6   5   3   3   3   4   4   0   4   4   3   3   3   5   6;
       6   5   3   3   4   4   2   1   1   3   4   4   3   3   5   6;
     6   5   3   3   4   0   1   1   2   1   1   0   4   3   3   5   6;
   7   6   5   3   3   4   1   0   1   1   0   1   4   3   3   5   6   7;
 7   6   5   3   3   4   3   1   1   0   1   1   2   4   3   3   5   6   7;
   7   6   5   3   3   4   1   2   1   1   2   1   4   3   3   5   6   7;
     6   5   3   3   4   0   1   1   0   1   1   0   4   3   3   5   6;
       6   5   3   3   4   4   2   1   1   3   4   4   3   3   5   6;
         6   5   3   3   3   4   4   0   4   4   3   3   3   5   6;
           6   5   3   3   3   3   4   4   3   3   3   3   5   6;
             6   5   5   3   3   3   3   3   3   3   5   5   6;
               6   6   5   5   3   3   3   3   5   5   6   6;
                 7   6   6   5   5   5   5   5   6   6   7;
                   7   7   6   6   6   6   6   6   7   7'
    id_name = 'assembly_id'         # automatically assigns assembly_ids
    assign_type = cell              # using cell mode
    exclude_id = 'dummy'            # don't assign ids to dummy assemblies
  []

  ### Step 4. Delete dummy assemblies by deleting all elements belonging to block 997.

  [del_dummy]
    type = BlockDeletionGenerator
    input = core
    block = 997                     # delete the elements in block 997 (these are the dummy blocks)
    new_boundary = radial           # rename the newly exposed outer boundary 'radial'
  []


  ### Step 5. Extrude 2D core to 3D.
  # The 2D plane will be extruded upwards into 12 "zones" consisting of varying actual thicknesses and meshing subintervals.

  [extrude]
    type = AdvancedExtruderGenerator
    input = del_dummy
    heights = '50.24 42.32 17.98 16.88 16.88 16.88 16.89 16.88 19.76 65.66 31.14 30.15'
    num_layers = '3 2 1 1 1 1 1 1 1 4 2 2'
    direction = '0 0 1'
    top_boundary = 998
    bottom_boundary = 999

    # This changes the block (subdomain) IDs on each axial layer from the original value (0,1,2,3,4,5,6) to something else
    # There are more than 7 materials in the problem so we introduce new block IDs such as 8,9,10,11,12 to account for different materials.

                      # The first row changes the bottom layer block ids 0 1 2 3 4 5 6 to block ids 12 12 12 12 12 11
    subdomain_swaps = '0 12 1 12 2 12 3 12 4 12 5 12 6 11;
                       0 9  1 9  2 9  3 8  4 9  5 10 6 11;
                       0 4  1 9  2 9  3 8  4 9  5 10 6 11;
                       0 4  1 1  2 2  3 8  4 3  5 10 6 11;
                       0 4  1 1  2 2  3 8  4 3  5 10 6 11;
                       0 4  1 1  2 2  3 8  4 3  5 10 6 11;
                       0 4  1 1  2 2  3 8  4 3  5 10 6 11;
                       0 5  1 1  2 2  3 8  4 3  5 10 6 11;
                       0 6  1 13 2 13 3 8  4 13 5 10 6 11;
                       0 6  1 14 2 14 3 8  4 14 5 10 6 11;
                       0 7  1 14 2 14 3 8  4 14 5 10 6 11;
                       0 15 1 15 2 15 3 15 4 15 5 15 6 11'
                       # The last row changes the block ids on the top layer
  []


  ### Step 6. Add reporting IDs ("plane_id") to each plane
  #  We can later query solution data by plane simply by integrating over elements with the same "plane_id".
  #  The axial heights here should match heights in the mesh.

  [plane_id]
    type = PlaneIDMeshGenerator
    input = extrude
    id_name = plane_id  # add reporting ids called 'plane_id'
    plane_coordinates = '0.000 50.240 92.560 110.540 127.420
                         144.300 161.180 178.070 194.950
                         214.710 280.370 311.510 341.660'  # elements between these coordinates will be labeled with the same plane_id
  []

  ### Step 7. Rename external boundaries to make it easier to reference in Griffin

  [abtr_mesh]
    type = RenameBoundaryGenerator
    input = plane_id
    old_boundary = '999 998'        # The old boundary '999' is renamed 'bottom'.
                                    # The old boundary '998' is renamed 'top'.
    new_boundary = 'bottom top'
  []

  # This is a placeholder in case you want to uniformly refine the mesh later on. It does nothing in this example.
  uniform_refine = 0

[]

(modules/reactor/test/tests/meshgenerators/revolve_generator/multi_revolve.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    element_type = HYBRID
    block_id = '100 200'
    block_name = 'block_tri block_quad'
    external_boundary_id = 300
    external_boundary_name = 'external_side'
    radial_intervals = 2
  []
  [rg]
    type = RevolveGenerator
    input = shg
    axis_point = '5.0 0.0 0.0'
    axis_direction = '0.0 1.0 0.0'
    nums_azimuthal_intervals = '6 6'
    revolving_angles = '150 210'
    subdomain_swaps = ' ;100 300 200 400'
    boundary_swaps = '300 500;10000 4000'
  []
[]

(modules/reactor/test/tests/meshgenerators/simple_hexagon_generator/sim_hex.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = 100
    block_name = hexagon
    external_boundary_id  = 300
    external_boundary_name = 'external_side'
  []
[]

(modules/reactor/test/tests/meshgenerators/reporting_id/hexagonal_id/core_reporting_id_exclude.i)

[Mesh]
  [assembly]
    type = SimpleHexagonGenerator
    hexagon_size = 5.0
    hexagon_size_style = 'apothem'
    block_id = '1'
  []
  [dummy]
    type = SimpleHexagonGenerator
    hexagon_size = 5.0
    hexagon_size_style = 'apothem'
    block_id = '2'
  []

  [core]
    type = PatternedHexMeshGenerator
    inputs = 'assembly dummy'
    pattern_boundary = none
    pattern = '  1 0 1;
                0 0 0 0;
               1 0 0 0 1;
                0 0 0 0;
                 1 0 1'
    assign_type = 'cell'
    id_name = 'assembly_id'
    exclude_id = 'dummy'
  []

  [del_dummy]
    type = BlockDeletionGenerator
    block = 2
    input = core
    new_boundary = core_out
  []
[]

[Executioner]
  type = Steady
[]

[Problem]
  solve = false
[]

[AuxVariables]
  [assembly_id]
    family = MONOMIAL
    order = CONSTANT
  []
[]

[AuxKernels]
  [set_assembly_id]
    type = ExtraElementIDAux
    variable = assembly_id
    extra_id_name = assembly_id
  []
[]

[Outputs]
  [out]
    type = Exodus
    execute_on = timestep_end
    output_extra_element_ids = true
    extra_element_ids_to_output = 'assembly_id'
  []
[]

(modules/reactor/test/tests/meshgenerators/flexible_pattern_generator/double_ext_boundary.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = 100
    element_type = QUAD
  []
  [fpg]
    type = FlexiblePatternGenerator
    inputs = 'shg'
    boundary_type = HEXAGON
    boundary_size = 3
    boundary_sectors = 1
    extra_positions = '0 0 0'
    extra_positions_mg_indices = '0'
    background_subdomain_id = 200
  []
[]

(tutorials/tutorial04_meshing/app/test/tests/adv_examples/mesh_revolve.i)

[Mesh]
  [shg]
    type = SimpleHexagonGenerator
    hexagon_size = 1.0
    block_id = '100 105'
    block_name = 'hex_tri hex'
    element_type = HYBRID
    radial_intervals = 2
  []
  [rg]
    type = RevolveGenerator
    input = shg
    axis_point = '5.0 0.0 0.0'
    axis_direction = '0.0 1.0 0.0'
    nums_azimuthal_intervals = '4 8 16 32'
    revolving_angles = '20 40 60 80'
    subdomain_swaps = ' ;
                       100 200 105 205;
                       100 300 105 305;
                       100 110'
  []
[]

Overview
Example Syntax
Input Parameters
Input Files